View Full Version : f64
Lenny Eiger
21-Jan-2011, 18:32
I have heard plenty of trash talk about the resolution of large camera lenses over the past few years. I have also heard that one should never close all the way down.
Well, I've just done the test for myself and I say its not true - at least for me - in the least. I pointed the camera out my front door and closed it down to f64. (I love depth of field.)
Now maybe some others want more sharpness than this example, but I am perfectly satisfied.... It's straight off the scanner, with no sharpening at all....
Saving for web made it way darker than I am going to print it, but take a look, and judge for yourself. I know I'm going to use f45 and f64 any time I want from now on, without fear that I'm losing something.
http://eigerstudios.com/sharpness64.html
Lenny
EigerStudios
John Brady
21-Jan-2011, 19:10
I stop way down always, rarely less than f45. I'll take the depth of field and image circle I get with my wide lenses at f64 any time.
Not sure what I may be missing out on, don't care.
www.timeandlight.com
If I have to choose between areas out of focus or perhaps a slight loss of sharpness, I'll take the latter. And it is nice to use process that one can only contact print with.
When enlarging to 16x20 from 4x5, using f16 did get me sharper prints than negatives taken at f64 (Caltar II-N 150/5.6).
Vaughn
Drew Wiley
21-Jan-2011, 20:06
It's simply a scientific FACT that diffraction affects sharpness at very small apertures. But everything obviously depends on the degree of print magnification
and everything else inbetween, and also on the precision of the film plane in the first place (ordinary filmholders don't hold film completely flat). In terms of personal technique, I generally stop down 4x5 lenses to f/22 to f/32 for the best combination of sharpness and depth of field, and 8x1O lenses from f/32 to f/64 - between these, it would be hard to note the difference in a 20X24 print, but distinctly noticeable in a 30X40 or 40X60 optical enlargement. Digital output is a little less fussy, since it can't resolve as much fine detail. Once again, I don't believe any of that "normal viewing
distance" bullshit - I'm referring to actual detail.
Drew Wiley
21-Jan-2011, 20:15
Well, I just looked at your actual images, Lenny - the size of a postcard, and on the
web a ball of fuzz that could have been taken with a pocket point n' shoot with vaseline over the lens. Sorry to be sarcastic, but this kind of presentation proves zero with respect to either large format technique or the quality of current lenses.
pdmoylan
21-Jan-2011, 20:20
DOF is like taxes, you only stop down to obtain the required circle of confusion, and with taxes pay no more than necessary. With skill, you learn to maximize hyperfocal point, use movements carefully and therefore use f-stops < f64; and one finds legitimate ways to reduce their tax burden. There are times when f64, with all the skill you have, is still necessary. William Neill would commonly stop down to F64 and Dykinga would shoot at F45 and beyond with many challenging images where maximum DOF is required. In such cases, ultimate sharpness (visual acuity) is less important than obtaining the results you need. I find that using mild wide angles on 4x5 (75mm - 110)with a foreground object that is very close to the lens while trying to obtain focus on it and the distant landscape is the time employ beyond f45.
Ed Richards
21-Jan-2011, 20:21
Lenny,
I have done comparison shots of the same set up. I find that seeing the loss at really small apertures requires some high frequency data in the pictures. Blades of grass, really small branches, that sort of things. Without that, it is hard to see a difference. Without a direct comparison, it would be hard to see any difference at all, at least with very sharp lenses. I also use whatever is necessary for sharpness demanded by the composition. I am trying to use more limited DOF and stop worrying about about overall sharpness.
Peter De Smidt
21-Jan-2011, 21:03
I usually prefer overall focus with my LF images over maximum sharpness, and so I wouldn't hesitate to us f64 if needed. But I don't make very big prints. If you'd like to, you might want to check out focus stacking.
Bob McCarthy
21-Jan-2011, 21:44
A perfectly good eyeball can only resolve 5 lpmm at normal viewing distance.
So defraction kicks resolution from 50 lpmm to 20 lpmm,
so what, a 4x enlargement still looks tack sharp.
So with an 8x10, you can still make a very large print.
Bob
Bruce Watson
22-Jan-2011, 07:00
I think it was Miss Manners who said something along the lines of: It's important to understand the rules so you can have fun breaking them.
In LF, I think it's important to understand how it all works, including diffraction. That way you can make intelligent and informed decisions during setup. It's all a tradeoff. Knowing what you are trading for what, and how much, can be the difference between good and excellent photographs.
That said, I often trade off some sharpness to get more DOF. And sometimes I'll accept more sharpness to get *less* DOF. It all depends on what I want to capture at the time.
Jim Jones
22-Jan-2011, 08:04
I agree with Drew. A rule of thumb for normal focal length lenses, regardless of format, is: for optimum sharpness, stop down so the aperture appears to have about a 1/4" or 1/5" diameter when viewed through the front of the lens. This gives a good balance between lens aberrations, DOF, and diffraction for many subjects. Long before digital calculators I went through the math for many lenses on several formats with pen, paper, and Rudolf Kinglsake's old Lenses in Photography. It was an education that many of us would find worth the effort. A calculator or computer can simplify the calculations. St. Ansel had good reasons to use f/64, and Weston could get by with smaller apertures with some of his subjects.
Steve M Hostetter
22-Jan-2011, 08:55
Obsession: The domination of one's thoughts or feelings by a persistent idea,image,desire,etc.
Drew Wiley
22-Jan-2011, 10:24
Steve - no obsession. Very practical. Although the ultimate performance of all lenses
us diffraction limited, we must frequently make wise decisions how to use this information. Sometimes f/64 is needed to make a certain lens cover the format
with movements. For example, I know exactly where this tradeoff occurs with a
250 G-Claron with my 8x10. You've only got so much room, and I know that at f/64
nobody will notice the slight degree of detail loss in a 16x20 or 20x24 print, but that
it start to be an issue in a bigger Cibachrome color print, for example. I know that if
I don't need as much depth of field or movement, I'll get better sharpness at f/32.
More often I work with longer lenses like 360 or 450, which have far more coverage
but obviously less depth of field. Today I'll be out with my completely rebuilt old
Sinar 4X5 testing each little repair, so the lens issues will be different, but by now I
know the parameters instinctively and don't even need to think about them. I'll just
know which f-stop works best.
Brian K
22-Jan-2011, 11:01
I've done extensive testing of nearly all of my lenses, using a stereomicroscope and I can state with complete confidence that there will be significant differences in sharpness between a LF lens shot at f 16 or 22 and say f45 or 64.
This difference didn't even require specific testing as it was very noticeable from my days as a still life photographer when I would most often shoot at f32 or 45 to get sufficient DOF and then on the rare occasions where I'd have to shoot at f64.
While an image shot at f64 will appear in focus and sharp given no point of comparison, once it's compared to an f 16 or f22 exposure of the same scene the differences are extremely noticeable under modest magnification.
Armin Seeholzer
22-Jan-2011, 11:12
occurs with a 250 G-Claron with my 8x10.
I did not know this lens does exist, I only have a 240 mm G-Glaron!
But only bootles get sharper at f 64 and f 90!
But if f 64 is needed I take it without any hesitation!
Cheers Armin
Lenny Eiger
22-Jan-2011, 11:34
To all those people trying to explain to me that diffraction is a fact, and try and school me on how to use swings and tilts, please stop. I am not an amateur, I've taught college courses in how to use large format cameras and I don't need the lessons. It only serves to annoy.
I was very careful to say that it proves it to me - and if its only to me, that's fine. FWIW, I think the bottleneck in the amount of sharpness is at the printer. I am also not shooting tabletop or other objects that require that kind of look. While some of you may prefer critical sharpness over DOF, I prefer DOF. This is an aesthetic choice.
What I see is that I have a lightning bolt clearly outlined on a very small droplet of water. I doubt that level of detail is going to make it thru the printer, it might be fun if it does - that's tomorrow's task. I am actually comparing 8x10 to 4x5 and 6x7, to see exactly what one can get and one can't on the same shot, with a perfectly exposed and developed neg.
FWIW, I just compared the 6x7 and there is simply no difference in the sharpness between 11 and 22 when viewing on photoshop at 100%.
I think the Rodenstock Apo S is a great lens. It has superb glass and an advanced coating. All I'm saying is that I am happy with the sharpness all the way down. No one has to follow me if they don't want to.
Lenny
Policar
22-Jan-2011, 11:53
I saw some very impressive 10x enlargements from 4x5 that were shot at f45. The photographer remarked that keeping everything in focus matters psychologically a lot more than having fine detail up close.
f64 isn't too bad on 8x10. Kind of equivalent (in terms of dof and diffraction) to f32 on 4x5, f16 on 6x7, or f8 on 135, I guess?
I'd be curious how f64 on 8x10 compares with f32 (at equivalent FOV) on 4x5 and how that compares with full frame digital.
Nathan Potter
22-Jan-2011, 13:45
The subject matter really determines the aperture I use and in combination with the degree of swing or tilt that I need to compose the image. And indeed I'll sacrifice resolution in the instances where I need overall DOF that can't be obtained by camera movements. Sometimes I'm disappointed with the results from a small aperture when trying to make a substantial enlargement so I just abandon the attempt and print to a smaller format. It is useful to have a feel for the degree of image degradation due to diffraction but the clearest guide is to do the simple calculation. I think in Lennys example he is just trying to get a feel for what an F/64 aperture will deliver with his combination. And yes, a comparison, at high mag., of say f/5.6 to f/64 with his dandy scanner would be most interesting. So Lenny, when you don't have anything else to do :D , go to it. :)
Nate Potter, Austin TX.
Bill_1856
22-Jan-2011, 17:00
The blowup looks pretty darned fuzzy to me.
Lenny Eiger
22-Jan-2011, 17:21
The blowup looks pretty darned fuzzy to me.
Well, you don't know what you're looking at. Maybe it doesn't translate on the web. However, I see tons of scans from lots of different photographers. Most are quite sharp. Very few of them look anywhere close to this good. When you blow things up on the computer you have to take into account the viewing percentage. There is nothing that looks perfectly great up at 100% - unless you are familiar with what you are looking at.
So far people have not quite understood what was being presented, others just thought they would re-iterate their positions and others thought I needed to be schooled. I say never mind. We can delete the thread. I'm tired of everyone being crabby, bitchy and egotistical.
Lenny
onnect17
22-Jan-2011, 17:59
Lenny,
Please, forgive the unsolicited bad humor expressed by some members. :)
To the point, allow me to give some feedback.
I also think the apo-sironar-s are great lens, I would say excellent. It's a matter of preference which aperture you use. Me?, I stay no smaller than f/22 and use movements.
Now, regarding the scanning. I don't think it makes any sense to "convert" to B&W if the film is already monochromatic. Just pick one channel (perhaps green have the less amount of noise) and drop the rest. Do not use the autofocus, I always got better results using the manual way.
Also, you should try 510-pyro or pyrocat-hd. Both are sharper than xtol.
My two cents.
Lenny Eiger
22-Jan-2011, 19:09
Now, regarding the scanning. I don't think it makes any sense to "convert" to B&W if the film is already monochromatic. Just pick one channel (perhaps green have the less amount of noise) and drop the rest.
Why do you imagine I haven't tried every different way of converting to b&w? I look at each channel and decide if there is anything I want in it. Most of the time I choose only one channel, but often its a mix of blue and green. I have often just dropped everything but green. I'm not new to this.
As to the rudeness, I am aways happy to hear about another way of doing something. There's an endless amount to be learned and we can all miss the most obvious things. However, the pedantic tone is really too much. It should be a conversation like - hey, have you ever tried this... or you know, one of my favorite techniques is such and such, does that work for you -- instead of everyone assuming that if someone posts a message they need serious help.
Do not use the autofocus, I always got better results using the manual way.
Are you using a Premier? Always happy to trade techniques with another maniac. However, I must say, my scans are razor sharp. You can ask any one of my clients. (Or me, my most critical client.) Still, I'll give it a whirl... and see what happens.
Also, you should try 510-pyro or pyrocat-hd. Both are sharper than xtol.
I shot a few extra sheets specifically to test this. Sandy's agrees to develop a film test for me. I doubt there will be any improvement, this stuff is already amazingly sharp, and sharper than the printer can print, but who knows -we'll find out. Sandy gets back from Africa in a week or so, I have a box already packed to send him for a comparison.
Lenny
Ed Richards
22-Jan-2011, 19:10
For your next goad to the list, let us know how that comparison between 4x5 and 8x10 works out.:-)
Lenny Eiger
22-Jan-2011, 19:14
For your next goad to the list, let us know how that comparison between 4x5 and 8x10 works out.:-)
Ed,
If a few people want to send me an email with their contact info, I'd be happy to keep them updated. I won't be posting the results here.
Lenny
Hi Lenny,
This has been a very interesting post -- for me :)
Out of curiosity I took your close up image and sharpened it [for the screen] using GIMP.
I am not a digital worker so ink printing is not in any way a consideration for me but the image I got considering yours is unsharpened in the posting is pretty good.
Thanks for posting as it does show a practical image and possibly what can be expected.
Can you post the two images again but sharpened to a level that might be acceptable?
Steve
onnect17
22-Jan-2011, 20:08
Lenny,
My only experience is with the Howtek d4000. It shares the basics of a drum scanner with the Premier, at 4000dpi max, using DPL.
I print 40x120s from 6x17 scanned at 4000ppi so I have to “milk” the negative. In my workflow the bottleneck could be the interpolation (not the printer) and QImage does a decent job. I do not use any sharpening and I doubt you would need it with the apo sironar s.
You said you scanned a B&W negative using the premier. If I understood correctly the information should be almost the same in the three channels. Except for noise and a little bit of contrast I can’t imagine any other difference. Also, 2666 dpi seems like a split 1/3 from 8000 dpi but I do not know the criteria used by Aztek to reach that resolution (dropping, average, interpolation, etc.) which could impact the final image.
The size of the pic with detail is around 1500x800. The corresponding fragment in the 8x10 should be around 4500x2300, so perhaps it lost some information during downsampling in PS. PS is not known for having the best interpolation algorithms.
Please let me know if I’m missing something.
Armando
Lenny Eiger
22-Jan-2011, 20:11
Hi Lenny,
This has been a very interesting post -- for me :)
Can you post the two images again but sharpened to a level that might be acceptable?
Steve
Steve,
I'm a little out of time today but I'll look at it again tomorrow. I think there's a problem in that this stuff is on computer screens, it's at a low resolution, etc. The scanner is looking in very close. The scan is a 2666 ppi and there are a lot of pixels. It does not need any sharpening. I usually do a .2 Radius at about 200-275. Printed, that image will be razor sharp. Hop on a plane and I'll be happy to show you... I was unaware the images would not be understood in their current form.
Lenny
Lenny Eiger
22-Jan-2011, 20:25
Lenny,
My only experience is with the Howtek d4000.
I print 40x120s from 6x17 scanned at 4000ppi so I have to “milk” the negative. In my workflow the bottleneck could be the interpolation (not the printer) and QImage does a decent job.
I haven't used QImage... so I can't really say. If they are 6x17's and not 6x7, then the 4000 would give you almost 90 inches at 300 dpi. It's not too far off. I am a little spoiled, I got the Premier to do the smaller film and its been sharper overall.
If I understood correctly the information should be almost the same in the three channels. Except for noise and a little bit of contrast I can’t imagine any other difference. Also, 2666 dpi seems like a split 1/3 from 8000 dpi but I do not know the criteria used by Aztek to reach that resolution (dropping, average, interpolation, etc.) which could impact the final image.
Please let me know if I’m missing something.
Armando
Well, sometimes it is identical in all three channels, but often it isn't. I use the 2666 because it gives me about 3 Gigs, which gets converted to 1 Gig when a single channel is chosen. Last month I made an 8000 ppi scan of an 8x10 for a guy who wanted to make a 25 foot wide print. It was 25 Gigs.... without any layers...
One is going to lose sharpness if you don't auto-track, or use the same number of pixels that matches the aperture. Roughly 4,000 six micron slices in an inch, or 2,000 13 micron slices. However,if you do auto-track, you won't have enough pixels and will end up interpolating, or simply having thing s be rough. I prefer to match to the grain and have the pixels I need. There are lots of trade-offs one way or the other...
Lenny
onnect17
22-Jan-2011, 20:52
25GB?
and I thought 2gb was a pain :D
Thanks for sharing this Lenny. I think that the people who are saying this crop is soft have no idea what size print it actually represents or how good of a scan it really is.
(I'm sure the same people will tell you how good their V750 could do!)
I've found myself needing f/32 from time to time on 4x5 to get the DOF I need. Often movements alone can't handle what I need, since, for example, I often shoot in urban areas with tall buildings or lamposts in the foreground and tall things in the background.
In a perfect world we'd all be able to shoot at the optimum aperture. But your test shows that you can get great results stopped down.
I may notice a slight softening at f/32 with my 150 Apo Sironar S, but it's minor, and in any event it's less objectionable than it would be to have parts of a photograph out of focus.
Armin Seeholzer
23-Jan-2011, 04:43
Would be interesting if every lens holds up same quality stoped all way down or if it would also give some strong differences!
I used my APO Ronar 360mm not to long ago at f 64 because it was needed and wanted and I was really surprised about the sharpness I got out of it and I had the impression it was a tick sharper then my 360mm Sironar N would have been at the same f stop!
So somewhere in the future I have to do a little test!
Cheers Armin
I'd agree about the Apo Ronar 360, though I've only used it at f/45...
sufficient for my needs at the time-
Regarding the picture in the op-
I presume the detail is of a section roughly one inch wide?
It has a pleasing tonality, but the issue of sharpness must surely be be read as a detail, a small part of a larger whole- as has been stated-
that detail, as a 1/100th part of a larger picture, must show impressive detail over a significant depth of field-
It also looks very clean, undoubtedly a very important quality, and it doesn't look particularly grainy on my monitor.
It doesn't look particularly sharp in itself, but it also doesn't contain the kind of high frequency detail that would be the true test of resolution- or at least, I can't see it...
Thanks for sharing this Lenny. I think that the people who are saying this crop is soft have no idea what size print it actually represents or how good of a scan it really is.
(I'm sure the same people will tell you how good their V750 could do!)
This claim reminded me of an earlier discussion, and some entrenched views regarding scanning, pixels, resolution, and diffraction-
maybe worth another look-
http://www.largeformatphotography.info/forum/showthread.php?t=44797&page=2
Given a correctly processed 8x10 negative, I'm quietly confident about pulling at least 72MP of usable data from my V750; the larger negative works to the strengths of the machine.
Brian K
23-Jan-2011, 08:51
All one need do is look at resolution charts to see, without any subjectivity that most modern LF lenses have better resolution at f 11, 16, and 22 than they do at f64. And decidedly so. It is not open for interpretation, it is fact.
That said, if one were to make a 2x print from an 8x10 negative shot at f64 versus a 2x print shot at f22, it would be hard to discern a difference. At greater magnifications however the differences would increase steadily.
With a 4x5 negative, and I think most LF shooters shoot 4x5 versus 8x10, the differences become evident sooner as the 4x5 requires twice the magnification that a 8x10 does.
A 5x enlargement of a 4x5 negative required to make a 20x24" print would make the differences between f22 and f64 apparent. Let's assume that you are using a high resolving film like T-Max 100, which resolves about 60-65 lp/mm. That resolution is about the typical limit for an excellent lens at it's sharpest aperture (there are lenses that resolve as much as 100 lp/mm but not in LF) so the resolution of the film is in itself not a limiting factor in most LF situations.
A lens that has a resolution of 65 lp/mm will commonly drop to a resolution between 20 and 30 lp/mm due to diffraction, so let's use 25 lp/mm as the resolution at f64. And if one assumes that the average resolution of the human eye is 6 lp/mm (estimates range from 5 to 14 depending on the distance and the color spectrum), then at 5x the resolution of the f64 lens will visibly fall off. For someone with excellent vision if one uses the 10 lp/mm factor, then focus will fall of at 2.5 times magnification.
Of course all of this depends on viewing distance. I've had my work enlarged billboard size and from the much greater distance that is required to view the whole image at that size, the image looks just as sharp as an 8x10 print in my hands.
But understand as a fact, that at f64 a LF lens will NOT resolve nearly as well as it does at f22. But understand further, that this loss of image quality might not be apparent depending on viewing distance and size of magnification. And one should have this knowledge and use it to determine if f64 serves the situation and outcome that you desire.
Drew Wiley
23-Jan-2011, 10:04
A 16x20 contact print taken at f/256 will probably look sharper than a 16x20 print
taken with a 4x5 at f/45. And as far as lens performance goes, all you have to do is
look up the mfg charts with most modern lenses from any of the four major mfg.
There's no substitute for field testing in terms of creative uses of lenses, but the mfg
has already done the hard work on an optical bench, with the variables accounted for. As far as presenting visual resolution evidence over the web, that's like attempting nuerosurgery with a crowbar and chainsaw.
Armin Seeholzer
23-Jan-2011, 11:21
All one need do is look at resolution charts to see, without any subjectivity that most modern LF lenses have better resolution at f 11, 16, and 22 than they do at f64. And decidedly so. It is not open for interpretation, it is fact.
This is all clear to me, but maybe there are lensdesigns which hold better then others way closed down, did somebody do such a test?
Cheers Armin
sanking
23-Jan-2011, 12:21
Brian, I think you made a mistake. According to this source http://www.flickr.com/groups/techtalk/discuss/72157606727844641/ .... Tmax is 150 lp/mm, if we can trust that.
The actual resolution of Kodak Tmax-100 can be found in the Kodak document F-4016. It is 63 lines/mm at TOC 1.6:1 and 200 lines/mm at TOC 1000:1.
See http://www.kodak.com/global/en/professional/support/techPubs/f4016/f4016.jhtml
Sandy King
Policar
23-Jan-2011, 12:39
I think depth of field as an aesthetic concern always trumps resolution. If all we only cared about was resolution, we'd be stitching digital images. Whether to stop down beyond what depth of field demands to get a long exposure versus using an nd filter is a valid question, and at that point you have to determine what you consider acceptably sharp, but if you're sacrificing the quality of the image for "image quality," that's the wrong priority.
The crop looks good to me, but it's been scaled down to 33%, I think. So that's 900dpi about? For 900dpi it seems a little soft but not terribly.
72 megapixels from 8x10 out of the Epson is kind of a disturbingly low figure... That's 18 megapixels out of 4x5. My $750 slr does that no problem.
Jiri Vasina
23-Jan-2011, 13:15
I think depth of field as an aesthetic concern always trumps resolution. If all we only cared about was resolution, we'd be stitching digital images. Whether to stop down beyond what depth of field demands to get a long exposure versus using an nd filter is a valid question, and at that point you have to determine what you consider acceptably sharp, but if you're sacrificing the quality of the image for "image quality," that's the wrong priority.
IMO very well said. There are much more variables at play that result in the success or failure of an image. Resolution (sharpness??) is only one of them...
Jiri
Lenny Eiger
23-Jan-2011, 13:52
Test, then know for sure what the acceptable range is. In the case of the Rodenstock 300mm apo Sironar S, f64 looks great to me.
This, of course, is the point. Testing one's lens and making a print is the easiest test you can do. All you have to do is take two pieces of film and expose them differently, then make prints, however you do it. My guess is that most of you will be quite surprised at the higher fstops given the standard line.... All lenses won't make it to 64, but I am sure a bunch of them will. The others might make it to 45....
The calculated numbers in a previous post about 72mp being the max for an 8x10 are patently ridiculous. They don't include the size of the chip, it's only parallel lines and numbers of pixels. I would say an 8x10 is more like 300, rather than the 568 it calculates to, but the statement is total conjecture, of course. It's only a measure of resolution, not particularly important to most LF'ers. After all, we use big cameras not because they are sharper, but because of their ability to render more textural information. Yet there is no measure for that, certainly not one that gets discussed regularly here. The measure for "quality" is strangely missing.
The only thing you can do, as Van has stated, is test.
Lenny
The crop looks good to me, but it's been scaled down to 33%, I think. So that's 900dpi about? For 900dpi it seems a little soft but not terribly.
72 megapixels from 8x10 out of the Epson is kind of a disturbingly low figure... That's 18 megapixels out of 4x5. My $750 slr does that no problem.
Well yes, quite.
At 900 dpi, it looks soft-
so why the extra effort in scanning to resolutions beyond the combined resolution of lens and film?
Or rather, why draw attention to it?
I think the point about combined resolution is that it takes account of your lens, aperture, and sensor, so reading a number off the box your DSLR came in is more about marketing than actual resolution.
There is a lot of good information in the thread I linked to, hard earned by those who have tested and calculated, and it might need a second reading to get to the finer details.
If you can get 18 DSLR megapixels from an image exhibiting similar depth of field for $750,
then I've wasted my money by buying a D700. What should I have bought?
I think depth of field as an aesthetic concern always trumps resolution. If all we only cared about was resolution, we'd be stitching digital images. Whether to stop down beyond what depth of field demands to get a long exposure versus using an nd filter is a valid question, and at that point you have to determine what you consider acceptably sharp, but if you're sacrificing the quality of the image for "image quality," that's the wrong priority.
Yes, of course. Perhaps the internet is not the best place to test these claims, a good print in a gallery, (where the picture is more important) will always have more value.
Perhaps we shouldn't discuss it at all, and just accept the numbers produced by those whose business it is to produce millions of pixels? Be they Epson or Nikon...
As I mentioned in my post, it's a good looking scan, very clean, and even at 72(combined) megapixels, highly detailed over it's whole area, not just the detail.
I'm willing to accept that the depth of field is covered by the aperture, at the stated print size, so I would be more than happy to accept 72 combined MP...
Perhaps we're too concerned with the large numbers produced by scanners and computers, to the point that we consider 72MP to be unacceptably small-
The calculated numbers in a previous post about 72mp being the max for an 8x10 are patently ridiculous.
Why? Have you tested, because I can imagine that if you'd like to support your claims, that a test like this would be quite easy to set up.
I have no interest myself, because, a: others more qualified than me will do it for me;
and b: I'm only interested in the picture, and I make no claims for my pictures, beyond what they look like.
I have far more faith in 72MP being a very large number than a very small number, because the denominator of the business we're involved in requires the use of ridiculously and increasingly large numbers.
72 is good, still larger than the combined resolution of any currently available digital back.
I believe my brief critique of the scan in my earlier post will get me off the hook regarding the important qualities (imo) of the image-
j
btw, 80 square inches at 900dpi is 64.8million pixels, if my multiplication is accurate...
Drew Wiley
23-Jan-2011, 14:53
Once you've scanned the print and applied PS controls like sharpening, you're learning a lot more about your digital skills and the idiosyncrasies of the digital pathway than about the lens. Cumulatively, this is can be important to personal
workflow, but pretty much obscures an objective evaluation of the lens in the first
place. In fact, once you shoot a piece of film you start losing critical information.
An ordinary film plane isn't flat, unless you've got astronomical-grade glass plates
or a vacuum back, and the characteristics of film dye clouds or silver grain have
an effect in themselves. Fortunately, a precisely aligned view camera acts just like
an optical bench; and with a good groundglass and serious magnifier we can learn
a lot about our lenses. For example, yesterday was a good day for long-distance
viewing, so I took my Sinar with its 28-inch bellows up a hill for infinity lens tests.
I rarely use my 450 Fuji C on 4X5 though often on 8x10, and a new thing I learned
it that it is extremely sharp at infinity even wide open. With a max aperture of f/12
and using only the center of a huge image circle, this was no surprise. But at that
kind of bellows extension even the slight gust of wind will mess up the image, and
it's nice to know that I can shoot that particular lens at very distant scenes a couple
of stops faster than I was previously accustomed to. Of course, I still want to stop
the lens down a little due to any potential uneveness of the film itself.
Yes, but given that wind is not, in itself, a lens aberration, and the use of a longer lens will be more forgiving to focal plane intolerance, due to increased depth of focus, is this point just a little bit moot?
Sharpening, when applied sympathetically, should not draw any more attention to itself than softening, so I'm willing to accept the best from any optical system-
even visual acuity over resolution, if you must...
Bruce Watson
23-Jan-2011, 15:10
I think depth of field as an aesthetic concern always trumps resolution.
+1. Always.
Brian K
23-Jan-2011, 15:39
A couple of things, when I wrote,"... one should have this knowledge and use it to determine if f64 serves the situation and outcome that you desire." it's purpose was to state that one should be aware of the resolution sacrifice one makes in using f64 but that sometimes f64 is what is required regardless of the consequence.
This was a common situation with me during my years as an advertising still life photographer. I routinely had to photograph cosmetics on 8x10 film at life size magnification, sometimes greater than life size. And even with all the movements available to me on a monorail view camera it was still not possible to get focus on all the planes of focus created by cosmetics standing, leaning, laying, moving back into perspective etc all in the same scene. Sometimes the camera would look like it was not even possible to have light pass through the bellows with all the compound tilts, rises, and swings in use. And it became necessary to shoot the scene at f64 or even f90. And while the scene would look in focus, it would not have the degree of sharpness that I was accustomed to. I would then have to weigh the final usage of this image.
If the image was merely going to appear in a magazine then f64 or f90 would suffice. If the image were to be used on a large sales display or poster in a store, with people being able to walk up to it and examine it closely, then the scene would be broken up into two images, with focus and aperture optimized for each, and then spliced together.
Drew Wiley
23-Jan-2011, 17:48
Joseph - Utterly not moot. It's the difference between a good shot and a wasted one.
Depth of field and camera shake are two different problems. In this case, on my 8x10 the 450 lens is supported by quite a bit of mass with respect to both the camera itself and a big tripod; in addition, the negative needs far less enlargement. On the 4x5 just a little vibration at this kind of extension with ruin the shot for any use I have in mind. Second, being sloppy with focus is symptomatic of inevitabley being sloppy with something else. Each of those little things add up to a cumulative effect. It's just like the folks who stop their enlarging lenses way down because they never bothered to correctly align their enlargers in the first place, or don't want to bother with glass carriers. If that suits someone's taste, that's their preference. But those are the kind of people who probably get their developer contaminated with fixer or have aphids crawling across the sensors in their DLSR's. Not my style.
Lenny Eiger
23-Jan-2011, 17:50
btw, 80 square inches at 900dpi is 64.8million pixels, if my multiplication is accurate...
FWIW,
10 inches x 2666 pixels is 26,660
8 inches x 2666 pixels is 21,238
The product of the two is 568,604,480 , or 568 megapixels...
That's only the number of pixels, and not the resolution... of course. Also, of course, I don't believe the resolution is less than 1/5. But that's just me.
Lenny
Drew, you mentioned using 28inch bellows and the unevenness of the film itself; my point was that depth of focus, the tolerance of film placement on the image side, is increased in that particular situation. I didn't mention Depth of field in relation to your post.
Each of the other factors you mention have little to do with the original topic, and just serve to add variables that will confuse things, so I won't go there-
Lenny, you've already said that 72MP is patently ridiculous, even though, by Policar's estimation, the image you've displayed has been downsampled to 900 spi- is this a fair estimation?
If it is, then we might not have hit bottom even yet; further downsampling might produce a sharper image than the detail displayed here. With the added benefit of increasing depth of field...
Perhaps posting the 2666 spi scan might help clear things up a bit-
maybe there is more information in the original scan that is being lost to compression? or some other reason?
The premise of your original post-
I have heard plenty of trash talk about the resolution of large camera lenses over the past few years. I have also heard that one should never close all the way down.
Well, I've just done the test for myself and I say its not true - at least for me - in the least. ...
- well, that, at least to me, is debatable- unless you refuse to accept debate.
Not that it matters to me much, I'll draw my own conclusions no matter how things are spun, based on the evidence presented-
However, since maximizing depth of field is the stated aim of a few here, it leaves me wondering why smaller formats aren't used- perhaps greater depth of field would be slightly easier to achieve that way-
You say - "The calculated numbers in a previous post about 72mp being the max for an 8x10 are patently ridiculous."
well, I don't find it ridiculous, but I'm open to being convinced otherwise-
if your 2666spi sample contains a lot more resolution than is shown in the reduction, then I'll be happy to accept it-
But as it is, I can only accept what I can see for myself-
If a microscopic scanning of the film grain is the purpose of the exercise, then I'm sure it has been a successful one- however, if the purpose is to disprove the existence of diffraction effects, well, on the evidence, I remain unconvinced-
The numbers in your last post have little meaning to me, you might have chosen 3000, or 4000 instead...
Of course, maybe I'm just adding to the trash talk-
onnect17
23-Jan-2011, 20:23
Lenny, here's a small sample of developers affecting sharpness in negatives.
Ken Lee
23-Jan-2011, 20:38
Lenny, here's a small sample of developers affecting sharpness in negatives.
What degree of magnification are we seeing here ?
Ken Lee
23-Jan-2011, 20:39
The actual resolution of Kodak Tmax-100 can be found in the Kodak document F-4016. It is 63 lines/mm at TOC 1.6:1 and 200 lines/mm at TOC 1000:1.
See http://www.kodak.com/global/en/professional/support/techPubs/f4016/f4016.jhtml
Sandy King
What does TOC stand for please ?
onnect17
23-Jan-2011, 20:59
What degree of magnification are we seeing here ?
Ken, Should be around 1mm between digits in a 35mm TMX, scanned in a Nikon V ED at 4000dpi. The better one is Pyrocat-HD. The other one is xtol.
TOC (Target Object Contrast)
I found it here --> http://www.agfa.com/sp/en/binaries/AVIPHOT%20COLOR%20X100_tcm221-42588.pdf
Lenny Eiger
23-Jan-2011, 23:56
Perhaps posting the 2666 spi scan might help clear things up a bit-
maybe there is more information in the original scan that is being lost to compression? or some other reason?
I am sure that would be better. If there was enough bandwith, I might. 3 Gigs is pretty large. When I look all the way into the grain, it is quite sharp. In fact, when one looks at the different micron apertures, there are some choices. The sharpest one usually does not print the best. It is the next one down, the one that smoothes the grain a bit, but still maintains the details in the image. When one looks at a lightning bolt on a droplet in that tiny a sample, that is holding said details that may or may not appear in the print at a large enough size. Using a sharper aperture will have more grain and anti-aliasing effects. The visual inspection that many are doing is an incorrect analysis. This is not about comparing bars. My test was not about the bars, it was not about resolution at all. I think talking about resolution is pretty meaningless. The only thing that matters is what you can do with the final print.
- well, that, at least to me, is debatable- unless you refuse to accept debate. Not that it matters to me much, I'll draw my own conclusions no matter how things are spun, based on the evidence presented-
I don't refuse, I'm just not that interested. You see, I have this piece of film here that I am looking at and all I care about is what I see as the result of my test. I don't need anyone else to help me analyze things, or figure out what happened, or whatever. I am very clear what the capabilities of my printer are, and I don't think it will differentiate the difference between different fstops, or if it will, it won't be dramatic enough for me to care.
As far as your own conclusions are concerned, I would hope you would draw your own. I have drawn mine.
However, since maximizing depth of field is the stated aim of a few here, it leaves me wondering why smaller formats aren't used- perhaps greater depth of field would be slightly easier to achieve that way-
That's not my aim. My aim in this test was to test the ability of different formats to render textural details in a print, in my system. The f64 was a small surprise that I found gratifying.
You say - "The calculated numbers in a previous post about 72mp being the max for an 8x10 are patently ridiculous." well, I don't find it ridiculous, but I'm open to being convinced otherwise-
if your 2666spi sample contains a lot more resolution than is shown in the reduction, then I'll be happy to accept it-
But as it is, I can only accept what I can see for myself-
Exactly. So take a picture, go get a scan from someone with a great drum scanner, who knows what they are doing, have them scan it while you are standing right there, helping set the parameters for how you would like to see it in the final print and you will have your answer. If you can't tell the difference at that time from a digital shot at 22 megapixels, or whatever, then you'll have your answer.
If a microscopic scanning of the film grain is the purpose of the exercise, then I'm sure it has been a successful one- however, if the purpose is to disprove the existence of diffraction effects, well, on the evidence, I remain unconvinced-
The numbers in your last post have little meaning to me, you might have chosen 3000, or 4000 instead...
I think you are adding to the trash talk. The reason I use those numbers is that what the scanner is actually scanning at. I have no interest in disproving anyone's ideas about diffraction or its existence, all I said was that I was surprised to find a lot more quality at f64 than what I was expecting given the word on the street about this.
If you want to prove diffraction is awful go do your own tests. You can consider my information totally anecdotal, that one person had a single result. Despite what it may seem, I'm really not here to argue about it.
Lenny
I think you are adding to the trash talk.
Thank you.
Bob McCarthy
24-Jan-2011, 07:32
FWIW,
10 inches x 2666 pixels is 26,660
8 inches x 2666 pixels is 21,238
The product of the two is 568,604,480 , or 568 megapixels...
That's only the number of pixels, and not the resolution... of course. Also, of course, I don't believe the resolution is less than 1/5. But that's just me.
Lenny
I agree with you Lenny, where does the 900 spi come from. Is he confusing resolution which is made in lpmm (30x30) with scan sample frequency.
There may not be 500 megapixels of information there, as that is scene/film dependent too. but there is the potential.
Bob
Ken Lee
24-Jan-2011, 07:59
Ken, Should be around 1mm between digits in a 35mm TMX, scanned in a Nikon V ED at 4000dpi. The better one is Pyrocat-HD. The other one is xtol.
Thanks for that. At 360dpi, we could enlarge that 4000spi sample by around 11X. That would be a roughly 10x17 inch print from 35mm. I can certainly see why we would want to use something like Pyrocat HD for roll-film ! The difference is way more than just graininess.
I see that your Photoshop screen capture, shows the images at 200% magnification. Perhaps I am mistaken, but doesn't that mean we are seeing scanner pixels at that point ?
(Whenever I look past 100%, that's what I see. The higher the % over 100, the more we see pixels, until eventually, the image looks like "tiles").
In the photos below, the sky appears to have grain in the second image - even though it's the same as the first image, just scaled to 200%.
http://www.kennethleegallery.com/images/forum/30-100.jpg
100% - Looks smooth
http://www.kennethleegallery.com/images/forum/30-200.jpg
200% - Exact same image - but looks ragged - sky appears "grainy"
Brian K
24-Jan-2011, 08:22
What does TOC stand for please ?
I'm not sure what the acronym TOC stands for but it relates to normal scene contrast. So you use the 1.6:1 figure for a truer sense of the films resolution. So the resolution of T-max 100 is 63 lp/mm, I believe in one of my previous posts in this thread I stated a range of 60-65 LP/mm.
As a side note, the late great TechPan had a resolution of 200 lp/mm at 1.6:1
onnect17
24-Jan-2011, 09:49
Ken,
The purpose of the side by side comparison was to show a loss of sharpness between developers, which probably could go unnoticed until you have to deal with the enlargement/printing and/or you scan with half the optical resolution (2000dpi). I think the idea is clear in the image.
You’re right, the original cropped fragment contained around twice the size (200%) and unfortunately the image gets altered with all the cut/paste and during the posting (I think it get resized to 650 x ?). If I have the numbers right what you see is “magnified” 1.5 times.
Still what appears like noise is not. 4000 dpi gets close to the size of the grain in this emulsion and due to the light source in the scanner the visible grain is sort of mixed with the scattered light. Good or bad, I doubt you could get much detail of the grain in tmx with an Epson scanner.
Too much dispersion/diffraction in the path, plus CCD.
I think the advantages of the stain in the negative for scanning are still undervalued. But that subject is good enough to start another thread.
What I can notice in you images is the product of compression artifacts (perhaps jpeg) after some sharpening and the resizing interpolation. With a clean scan I feel confident enough to resize 20x without any sharpening and/or grain filtering.
Grain is my friend, even if I want him smaller.
You're more than welcome to take my V ED for a week in a trip to western mass. :)
Ken Lee
24-Jan-2011, 10:21
Thanks for explaining that. I'm sold :)
Thanks for the offer. I don't have any 35mm to scan at this time. I had one of those scanners. They are terrific. I wish I hadn't sold it.
Kirk Gittings
24-Jan-2011, 10:56
Lenny, here's a small sample of developers affecting sharpness in negatives.
What is the chemical mechanism where one gets more pronounced grain (and what appears to be sharper grain in the Xtol example) AND less sharpness in the DETAILS of the letter image? This seems counter intuitive me.
onnect17
24-Jan-2011, 11:08
What is the chemical mechanism where one gets more pronounced grain (and what appears to be sharper grain in the Xtol example) AND less sharpness in the DETAILS of the letter image? This seems counter intuitive me.
Kirk, the grain in the xtol is not sharper, just bigger. It's sharper look in this post is a product of down sampling/grain size/ scanning resolution being close to multiple of each other.
I'm trying not to get in the subject but I think the big difference here is stain vs not stain. The scattered light in the Nikon sort of amplifies the effect. IMO, the stain reduces a lot of the dispersion and diffraction occurring around the “clean” grain and reaching the neighbor cells in the CCD.
Armando
Ken Lee
24-Jan-2011, 11:42
Are the stain molecules, simply smaller than film grain clumps ?
onnect17
24-Jan-2011, 11:59
Are the stain molecules, simply smaller than film grain clumps ?
That's a good question. I don't believe the stain is in any form of clumps like the silver but if it is I'm sure is at least a hundred times smaller, enough to ignore it.
Ken Lee
24-Jan-2011, 12:09
In his article Pyro Staining Developers (http://unblinkingeye.com/Articles/PCat/pcat.html) on the Unblinking Eye web site, Sandy King quotes Steve Simmons as follows (bold emphasis mine):
“In other words, there is no general overall stain that would act like fog, but a stain that acts like extra density and this stain increases as it goes up the tonal scale. Consequently, the film’s high value silver densities are thinner than with a conventional developer, and the extra density needed to produce the high value tones is created by stain. These ‘thinner’ high value densities in the negative can produce wonderfully clear delicate high values in the print, unlike any tone that can be produced by a non pyro film developer.”
He goes on to state the following:
"Highlight separation, sharpness and acutance are increased because Pyro gives more pronounced edge effects than other developers. This is due to the fact that there is very little migration of silver halide during development, resulting in a more precise reduction, which enhances sharpness, and because Pyro tans and hardens the gelatin during development, thereby reducing the effects of irradiation (scattering of light in the film emulsion) and infectious development (spreading of silver development beyond the exact image boundaries)."
onnect17
24-Jan-2011, 12:29
The grain is almost invisible in the near white tones. In fact, I usually extend the development knowing the stain will be higher and then recover the gamma in PS.
Sometimes the edge effects are associated with stand development but both films were processed in a jobo at full speed. Also a 3rd one developed in 510-pyro is very similar to the one in Pyrocat-HD.
falth j
24-Jan-2011, 12:34
“wmokrynski” in another post titled:
"Focus" problem that is driving me insane”,
seems to be having trouble with differing focus and out of focus areas on his negatives, and cannot understand the cause...
some posters are saying negative pop,
yet other posters are intimating that ‘diffraction’ lens opening size is always something one must always consider in the issue of overall image sharpness…
What I’m reading in this post f64, Lenny seems to be saying that for himself, he has not found this to be the case…
and et al…
is that diffraction, size of lens opening are not of importance, in the issue of image sharpness,
while other indications imply that lens design and diffraction are least when the lens is wide-open…
see the article in Luminous Landscape on Diffraction:
www.luminous-landscape.com/tu...fraction.shtml
Much to digest and apparently I am seeing two differing points of view, or two different area of concern/problems ?
Lenny Eiger
24-Jan-2011, 12:58
What is the chemical mechanism where one gets more pronounced grain (and what appears to be sharper grain in the Xtol example) AND less sharpness in the DETAILS of the letter image? This seems counter intuitive me.
I'll try and explain this succinctly, I'm sure others here could do better....
This all has to do with the right balance. I appreciate the example being posted, however, I generally re-check everything done in 35mm, as it seems to be different film, perhaps the same formulation, but thinner emulsions, and there are plenty of other factors I am sure I am not aware of..
Developers are primarily a developing agent, and a degree of alkalinity. (Usually.) The more alkaline, the more active the developer will be. Then there's the wash of clearing mechanisms, in the old days this was usually sodium sulfite. Then there's a few techniques, two bath development, multiple developer iterations, agitation strategies, roller base vs trays and a bunch of other things that affect the overall result.
The two main families of developing agents are Metol and Phenidone. There are others, Hydroquinone, Pyro, Glycin and a bunch more. Last I looked, Xtol is based upon Phenidone, altho' it is some variant thereof.... Metol development is what we are used to in things like D-23 and D-76. Phenidone has the action of coating the edges of the grains with dark, which often outlines the grains. Take a look at the etched grains of development like Rodinal, for example. If this effect is limited, Phenidone can be a terrific developer.
The one difference that short-circuits my general understanding is that Xtol is not based upon an alkaline activity controller, but uses the opposite, specifically ascorbic acid. (Maybe from orange juice! Go figure.)
When looking at onnect17's example, a couple of things that come to mind. Mainly, his Xtol was simply more active than the Pyro. This means that it went thru like a roto-rooter. It washed out silver between the grains. It also did not articulate the darker areas as well. That's very interesting. We tested many developers against Xtol, altho' we left Pyro out of our testing, and Xtol won every contest - in our darkroom. That last comment - in our darkroom - is important...
If the strength of the Xtol was matched exactly to the Pyro, would it be closer? Maybe, but probably not. One might imagine so if you looked at the dark letter and imagined that it was bleeding, but the truth is the other letters are lighter and it doesn't look like that.
Pyrocat is a fairly weak developer in most formulations. It also doesn't etch the edges of the grains like Phenidone does. There is probably a difference in the agitation, or in the way the developer-film combo responds to additional agitation.
I'm not ready to say that Pyro is simply sharper. Not until I test it for myself... But it might be.. and there are other benefits. It's important to me to be able to develop a number of sheets at a time, as in a Jobo, and not use development times like 22 minutes, if it can be avoided. That has to do with my shooting style... and what I think I need.
I acknowledge onnect17 for doing his own testing. Personally, I won't ever use 35mm for anything. The Mamiya 7 is small enough to carry around as if it were a 35 and you get a decent-sized piece of film. That's a very personal choice, of course. But it also colors what I will see in the printing. My last test was about finding the edges. I'm almost complete.....
I hope this helps and, even more, I hope its what you were asking...
Lenny
Drew Wiley
24-Jan-2011, 13:04
Faith - all of the above are real factors. Anyone who thinks they are just differences of
opinion is full of *%@#! Plus this discussion has entered into a whole other arena of
digital factors which are not directly lens related, but to how the film data translates
via workflow, and how to simulate a sharp image rather than check for actual lens performance in the first place. And now apparent grain effect vs actual, which often depend on the mode of printing etc. One needs to study these issues one at a time to
get ahold of them, rather than lumping together a cumulative sum and guessing what
is happening. I should probably just shut up because I don't dovetail with the geek
mentality very well.
Drew Wiley
24-Jan-2011, 13:13
Ken - since the different pyro developers have somewhat different effects in relation to the color of exposure light, what I sometimes do in cases of a developer new to me
is to view the magnified image through a deep tricolor filter. This gives an approximation of how things will look to the printing medium itself, relative to its own
sensitivity, of course. I find it interesting that my precision Peak easel magnifier came
with a deep blue accessory filter as standard equipment, back when most papers were
just blue-sensitive. But it comes in handy sometimes now for evaluating the effect of
pyro stain on extremely fine detail - more an issue with smaller formats where the film
grain is actually apparent. With variable-contrast papers there are significant differences between the kinds of stains produced by the yellow-green of PMK, for
example, and some of Sandy's pyrocat formulas, and the W2D2 approach. I imagine
this would have a significant effect in scanning for a single color channel too, which
some folks do if order to read through the stain.
Ken Lee
24-Jan-2011, 14:52
"Pyrocat is a fairly weak developer in most formulations. It also doesn't etch the edges of the grains like Phenidone does".
Perhaps you were referring to Pyrocatechin alone.
Pyrocat HD contains Phenidone. See http://unblinkingeye.com/Articles/Pyrocat/pyrocat.html
Lenny Eiger
24-Jan-2011, 14:58
Perhaps you were referring to Pyrocatechin alone.
Ken,
I used to use PMK all the time... back when I was doing trays. I used PyroCat a couple of years ago and failed miserably with it. However, I hasten to add, it was totally my fault... I'm going to try it again...
Lenny
sanking
24-Jan-2011, 15:56
When looking at onnect17's example, a couple of things that come to mind. Mainly, his Xtol was simply more active than the Pyro. This means that it went thru like a roto-rooter. It washed out silver between the grains. It also did not articulate the darker areas as well.
Lenny
You would want to always compare developers with a given film at the same contrast. Frankly the two samples look pretty close to me in contrast, though one would have to measure the original negatives to be sure.
But I am fascinated by your comment, "it went thru like a roto-rooter. It washed out silver between the grains? " I am having a real problem getting my mind around how a developer washes out silver! The action of developers is such that they reduce various forms of silver salts to silver metal. I don't believe there is any mechanism by which a developer washes out silver. If a developer is more energetic it simply performs the action of reduction faster but there is no roto-rooter action going on.
Sandy
Lenny Eiger
24-Jan-2011, 16:16
But I am fascinated by your comment, "it went thru like a roto-rooter.
Sandy, This comment is relative to what I think I understand about the process at a molecular level. What was explained to me many years ago (and from my reading the the Photochemistry book) is that during exposure the photons affect only a few molecules at the top of the emulsion, and that the developer that comes after drills down into the emulsion following the tracing of the those affected molecules. It was explained in fairly dramatic terms. Roto-rooter came to mind. When things are considerably more active, this redox reaction is more intense and there are different effects caused by this change.
Now, of course, that was a long time ago. They could have re-written the books entirely based on better information and I could be all wrong... that's why I said its what I think I understand...
It washed out silver between the grains? " I am having a real problem getting my mind around how a developer washes out silver! The action of developers is such that they reduce various forms of silver salts to silver metal. I don't believe there is any mechanism by which a developer washes out silver.
In that instance, I was speaking about developers vs developing agents. Some developers which have a lot of sodium sulfite, for instance, wash out spaces between the grains, or wash off the edges of the grains so that the grains are smaller. They are called solvent-type developers because of this. Looking at the grains in question, it appeared that the developer used has some sort of mild solvent action going on. I suppose it could also be something else.
I don't pretend to be a chemist... I was trying to answer a question, and not to be the authority on this subject (which I am not). Clarification is welcome.
Lenny
sanking
24-Jan-2011, 17:39
Lenny,
There is no question but that the latent image that is formed during exposure must be amplified many thousands of times during development to form a strong visible image. I have no problem with that idea if that is what you mean by "roto-rooter." However, I don't find anything in the literature about silver being washed away. This simply does not happen, at least by any understanding I have of the development process.
However, I don't think any of this has anything to do with why pyro developers produce sharper negatives. That is due primarily, IMO, to the fact that pyro developers tan the image site and this results in a more precise reduction because there is very little migration of development outside of the image site.
Several years ago I compared several pyro staining and tanning developers with several traditional non staining developers. In every case the pyro developers produced better resolution by about 15% to 20% compared to the traditional developers. The issue is that you have to go to a fairly high magnification to appreciate the difference.
Sandy
onnect17
24-Jan-2011, 18:07
Lenny,
Just to clarify some points.
I used xtol stock solution. According to Kodak it produces the smallest grain.
510-pyro contains ascorbic acid and phenidone and the results were very close to the pyrocat-hd.
You can accommodate your preferences regarding the time spent in front of the jobo. Either 22 minutes, 1hour, or the 10 minutes I used here.
The reason I use 35mm for the tests is simple. I expose a roll under the same conditions so I can use cuts to compare different developers. It’s quick, cheap and fast to scan.
As a format, 35mm is as good as any other. The only thing missing is the ground glass :)
I use 4x5 for the flatness of the film and when I want over 300 dpi in 44” paper. It’s cheaper that 8x10, more emulsions available and produces similar information at 4000dpi than a 8x10 at 2000dpi.
Allow me to suggest to stay with xtol if you are happy with the results and even try f/128. After all that was the reason you started the thread.
onnect17
24-Jan-2011, 18:14
Several years ago I compared several pyro staining and tanning developers with several traditional non staining developers. In every case the pyro developers produced better resolution by about 15% to 20% compared to the traditional developers. The issue is that you have to go to a fairly high magnification to appreciate the difference.
Sandy
Hi Sandy,
If you have any notes about it you should write an article. The subject is very interesting.
Lenny Eiger
24-Jan-2011, 18:18
Lenny,
Just to clarify some points.
I used xtol stock solution. According to Kodak it produces the smallest grain.
I would be interested if this were true. It runs counter to what I think I understand.... it would seem a bit strong at full concentration.
I use 4x5 for the flatness of the film and when I want over 300 dpi in 44” paper. It’s cheaper that 8x10, more emulsions available and produces similar information at 4000dpi than a 8x10 at 2000dpi.
This point I would disagree with. I racked my brain over this for years. Some part of me was insistent that "it should work" and yet the prints are strikingly different. Film real estate is a huge factor in textural reproduction. However, before anyone responds, let me finish my test... this is what its really about... what can 4x5 and 6x7 actually do...
Lenny
Drew Wiley
24-Jan-2011, 18:50
Lenny - you should email Joseph Holmes over in my neighborhood. He's looked at this kind up question rightside-up, upside-down and sideways, and is as nitpicky with
film and lenses as I am, but also extremely knowledgeable with large format digital
output. Just because I personally have a traditional darkroom bias doesn't mean that
I haven't had fascinating discussions with these kinds of guys about the options.
Lenny Eiger
24-Jan-2011, 19:03
Lenny - you should email Joseph Holmes over in my neighborhood. He's looked at this kind up question rightside-up, upside-down and sideways, and is as nitpicky with
film and lenses as I am, but also extremely knowledgeable with large format digital
output. Just because I personally have a traditional darkroom bias doesn't mean that
I haven't had fascinating discussions with these kinds of guys about the options.
I've spent time talking to Joe. Nice guy.
Of course, he is after a very different result than I am... I don't actually need Joe's help in this. I am also extremely knowledgeable with digital output. I have two 12 color printers, one for color and one for b&w.
Lenny
onnect17
24-Jan-2011, 19:15
I would be interested if this were true. It runs counter to what I think I understand.... it would seem a bit strong at full concentration.
In publication J-109 titled "KODAK PROFESSIONAL XTOL
Developer", page 2, second column, 3rd paragraph, it reads:
Dilution at 1:1 will provide slightly greater film speed,
enhanced sharpness and shadow detail, and slightly more
grain.
You can access the publication here:
http://www.largeformatphotography.info/forum/newreply.php?do=newreply&p=678173
Lenny Eiger
24-Jan-2011, 19:43
In publication J-109 titled "KODAK PROFESSIONAL XTOL
Developer", page 2, second column, 3rd paragraph, it reads:
Dilution at 1:1 will provide slightly greater film speed,
enhanced sharpness and shadow detail, and slightly more
grain.
Yes, I concur with the paragraph you reference. I found it as well. Here:
http://www.kodak.com/global/en/professional/support/techPubs/j109/j109.pdf
However, in your previous post, you suggested that you use Xtol in a "stock" solution.
I will also say that manufacturer recommendations have always been just a guide, and not necessarily something I take as truth. Most of the people here, for instance have set their own film speed over the years.
Lenny
onnect17
24-Jan-2011, 19:48
Yes, I concur with the paragraph you reference. I found it as well. Here:
http://www.kodak.com/global/en/professional/support/techPubs/j109/j109.pdf
However, in your previous post, you suggested that you use Xtol in a "stock" solution.
I will also say that manufacturer recommendations have always been just a guide, and not necessarily something I take as truth. Most of the people here, for instance have set their own film speed over the years.
Lenny
Help me here. If I want the smallest grain I should not use the 1:1 dilution. The stock is the one recommended, right?
Lenny Eiger
24-Jan-2011, 19:55
Help me here. If I want the smallest grain which dilution I should use? Stock right?
You're right... I'm too tired, I guess I can't read anymore. I think I read what I expected it to say....
It doesn't make sense. But its also an ascorbic acid thing so maybe its not supposed to make sense. I'd have to test it to really believe it. However, good film speed, sharpness and shadow detail also sound good.
Lenny
srbphoto
24-Jan-2011, 21:08
My rule of thumb:
f22 and be there, 10 minutes early!!
sanking
25-Jan-2011, 06:04
You're right... I'm too tired, I guess I can't read anymore. I think I read what I expected it to say....
It doesn't make sense. But its also an ascorbic acid thing so maybe its not supposed to make sense. I'd have to test it to really believe it. However, good film speed, sharpness and shadow detail also sound good.
Lenny
Lenny,
Nearly all developers that contain a fair amount of grain solvent (sodium sulfite) give finer grain when used straight (or stock solution). I don't know the exact formula of Mytol but I am fairly certain that it contains quite a bit of sodium sulfite. The same is true of D76. Stock solutions give finer grain but diluted 1:1 or 1:2 you get more grain but also slightly more acutance.
So finer grain with the stock solution is exactly what we should expect with Xtol (and with D76 and all developers that contain a lot of sodium sulfite). This is Developer Theory 101.
Sandy
Peter De Smidt
25-Jan-2011, 07:04
I've found that using stock Xtol does lead to slightly finer grain than using a more dilute version.
Lenny Eiger
25-Jan-2011, 10:07
Lenny,
Nearly all developers that contain a fair amount of grain solvent (sodium sulfite) give finer grain when used straight (or stock solution). I don't know the exact formula of Mytol but I am fairly certain that it contains quite a bit of sodium sulfite. The same is true of D76. Stock solutions give finer grain but diluted 1:1 or 1:2 you get more grain but also slightly more acutance.
So finer grain with the stock solution is exactly what we should expect with Xtol (and with D76 and all developers that contain a lot of sodium sulfite). This is Developer Theory 101.
Sandy
Well, it's a long time since DT 101 and I haven't been teaching for quite some time, so its only what sticks in this brain of mine. However, I do remember that "fine grain" didn't necessarily mean fine grain that way I wanted it to. If it means the grains are smaller, then they are farther apart, resulting in a more grainy look. This was the party line when I was learning this. It seemed duplicitous of the developer companies to state that something was fine grain - which made me think this assumption may not be true, either. What is your take on this...
I was always interested in a denser grain pattern - imagining that the image would be smoother.
Lenny
Drew Wiley
25-Jan-2011, 10:11
Sandy - I only use conventional developers for lab applications and not general shooting, but I've got to agree about D76 having greater acutance at 1:1 than standard; but I wonder if this is just a function of longer development time and the
way the grain forms? Certainly edge acutance appears a little better. D76 is something
I frequently use for a distinct upsweep curve in films like FP4, for what I call an
upsweep mask in color reproduction. Since this is an unsharp maks in the first place,
I'm concerned about the grain only if it is capable of appearing gritty in the final
color print, which it isn't, even in enlargements from 35mm. But that's more a function
of how it interacts with the dye cloud of the color original. I running some tests this
week where it must dovetail with black-and-white film interpositives, which might
give a different practical result. It's a non-issue with the 8x10 format I generally work
with, since print magnification is so modest, but I still want to know just in case I
do something analogous someday with small format. A scanner would, of course, see
things differently, and even the type of anti-newton glass or spray involved seems to contribute to the final effect in high magnifcations.
sanking
25-Jan-2011, 10:24
Grain is a bit difficult to get a handle on because sometimes when it is very prominent it is not unpleasant, and at the same time when very it is very smooth it can be aesthetically unpleasing. So I don't really know what to say other than the obvious fact that grain is going to look different depending on whether you wet process (and in that case also dependent on the light source, sensitivity of the paper, and color of the negative if a pyro one) or scan to print digitally. And there is probably a greater variation in grain look with scanning than with analog printing because the difference in scanners and operators will give results that are in the middle of the board, and off the board. I have compared the same negative scanned by me with my Eversmart Pro and by other folks with several different drum scanners and the look of grain is remarkably different.
Bottom line, you are right to do your own testing with your scanning and printing work flow because it is likely to give results that are specific only to you. Just don't be surprised that others may have totally different opinions based on the reality of their own work flow.
BTW, you can send me the test film when you like but I will probably not be able to get to it until after February 7 as I am teaching a workshop next week (five straight days) to someone who wants to learn it all, i.e. scanning technique, digital work flow, pt/pd printing and carbon transfer printing.
Sandy
bob carnie
25-Jan-2011, 11:08
However, I don't think any of this has anything to do with why pyro developers produce sharper negatives. That is due primarily, IMO, to the fact that pyro developers tan the image site and this results in a more precise reduction because there is very little migration of development outside of the image site.
Several years ago I compared several pyro staining and tanning developers with several traditional non staining developers. In every case the pyro developers produced better resolution by about 15% to 20% compared to the traditional developers. The issue is that you have to go to a fairly high magnification to appreciate the difference
Sandy
I agree with these comments completely, the hardening effect containing the migration is most important in the highlights , which allow the shadow detail to come up.
We have processed thousands of runs of different film and developers and completely agree with Sandy's findings.
We have switched countless photographers to Pyro due to this tannin effect.
pdmoylan
25-Jan-2011, 11:46
What began as a general discussion about DOF has evolved into B&W work flow and biases for maximizing sharpness. With all due respect to those who have acquired nuanced knowledge of how to get an ultimate print, perhaps we could contain ourselves and start a new thread when we have run the train off the track. It is also unfortunate that there has been no discussion or at least referrals/links about/to related issues to the original thread (i.e. hyperfocal focusing and using movements to reduce stopping down to F64).
Drew Wiley
25-Jan-2011, 12:12
Lenny - I certainly wasn't trying to imply that you weren't expert in your line of
processing images, and hope you understand that my sarcasm at times is more just
conversational spice than any attempt to be rude. I apologize if it sometimes comes across otherwise. One thing I find out from time to time is how such conversations with others help us look at solutions from a little different perspective from our own; and that is a real benefit of forums like this. I sometimes get my big nose into these
quasi-digital threads, but the interaction helps me translate for some of my friends
or students who live in more of a digital + darkroom schizophenia than I personally
do.
Sandy - I only use conventional developers for lab applications and not general shooting, but I've got to agree about D76 having greater acutance at 1:1 than standard; but I wonder if this is just a function of longer development time and the way the grain forms? ...
As I understand it, it is due to the action of the silver solvent (Sodium sulphite) in the developer -- the solvent has less effect when diluted, thus the grain has more defined edges than with film developed at full strength.
I use to use Microdol-X at 1:3 with Pan-X -- seemed to give me a nice compromise between fine grain and acutance.
Lenny Eiger
25-Jan-2011, 12:24
BTW, you can send me the test film when you like but I will probably not be able to get to it until after February 7 as I am teaching a workshop next week (five straight days) to someone who wants to learn it all, i.e. scanning technique, digital work flow, pt/pd printing and carbon transfer printing.
Sandy
Sandy, no worries. I'm not in a hurry. I'm printing the 810's now and want to make sure I can even get the effect I want before I send it. Anything you make better will only add to what we are learning... it may make it better, won't change the behavior of the current test's parameter...
Tx,
Lenny
Drew Wiley
25-Jan-2011, 14:13
Vaughn - that seems to make sense. I haven't used Pan-X forever, but it was back in
the brief D23 era when I was experimenting with high sulfite developers. Now if I want
something old and oversaturated with sodium sulfite it would be a salad at Denny's.
Lenny Eiger
25-Jan-2011, 14:27
Lenny - I certainly wasn't trying to imply that you weren't expert in your line of processing images, and hope you understand that my sarcasm at times is more just
conversational spice than any attempt to be rude. I apologize if it sometimes comes across otherwise.
Drew,
Apology accepted.
I don't pretend to know everything. It's impossible to learn all the aspects of this game. I can guarantee you that Joe Holmes knows more than I do about mapping color spaces. I can also guarantee you that I know more than he does about a 12-color d'vinci system and getting the color right on matte papers like PhotoRag. I'm not saying he couldn't figure it out - he certainly could. But I happen to know he hasn't. I use ErgoSoft's StudioPrint, have for years, and some times when I ask ErgoSoft a question I learn something. Sometimes they say things like - you're the only person we know that's checking this out with our software - let us know how it goes.
I am also driving a second 12-color printer with StudioPrint using b&w inks. That's 6 warm, 6 black and all 12 for neutral. I don't think there is anyone else out there mixing 12 channels of b&w, split toning them when necessary, etc., except for maybe Jon Cone... If there is, I'd love to know them and trade what we've found out.
Now all of this doesn't help me making a carbon print. I think I've made one or two in my life... But I'm not pretending to be an expert on carbon prints.
I am analyzing another neg I shot at f64. It's amazingly sharp on my monitor. I'll grant you that my example on the web may not have been useful enough. However, in general I think we all have to be clear when responding whether or not the person is actually asking a question, or asking for help, and finally, what their level of experience is....
Lenny
Drew Wiley
25-Jan-2011, 14:47
Lenny, I don't think Joe has worked seriously in black-and-white for decades, though
there are a few people who approach black-and-white inkjet itself on a color-mapping
premise, maybe not critically, but at least as a practical workflow. I've outdistanced Joe for many years when it comes to color darkroom technique. But sometimes it's interesting to debate the pros and cons with him, or with the other guru across the Bay, Ctein, who works in both traditional and digital color. So far, none of my own
proselytes have opted for digital black-and-white, preferring to do that kind of imagery
the traditional way. Color is a different story, since a serious color darkroom is a far
more involved commitment. But it's nice to have yet another valuable resource in the
vicinity, and if good medium-format scanners do again become available, I have a friend or two who might seek your advice. Thanks.
onnect17
25-Jan-2011, 14:52
Sandy,
Where's the workshop?
Armando
I shouldn't be doing this...
I am analyzing another neg I shot at f64. It's amazingly sharp on my monitor. I'll grant you that my example on the web may not have been useful enough. However, in general I think we all have to be clear when responding whether or not the person is actually asking a question, or asking for help, and finally, what their level of experience is....
I'm pretty confident that remark is directed at myself, and those who commented that the image posted was pretty fuzzy.
Lenny, you've claimed 300MP resolution for the file you posted-
then subsequently claimed that resolution was unimportant.
The terms 'Sharpness' and 'Resolution' have been used interchangeably since this thread segued into a discussion about film and digital processing.*
When some people challenged your claims about the detail picture you posted,
you reacted in a childish and rude manner, indulged in personal slur, and requested that the thread be deleted.
It seems as if actual resolution is no more than a belief system around here,
and unsubstantiated claims are defended by rubbishing those who choose to disagree.
It is also unfortunate that there has been no discussion or at least referrals/links about/to related issues to the original thread (i.e. hyperfocal focusing and using movements to reduce stopping down to F64)
I did reference a thread on resolution in an earlier post, even those believers who worked out that we were looking at a soft image at 900dpi couldn't accept that an 8x10 scan of an image shot at f/64 could be less than 72MP.
This whole area is a belief system, and relies on acts of faith, and the rebuttal of the laws of the universe, the casting out of non believers, and the impugning of their experience.
Other threads on the same subject have descended into personal slurs by the faithful and their followers, and valuable contributors leaving the site, after beating their head against a brick wall for too long.
As you said at the top of the thread, there has been a lot of shite talked about big lenses and resolution over the years.
joseph
* btw, this thread's title is f/64- if a developer can provide enhanced resolution when used with a particular film, isn't that negated if the resolution isn't projected onto the film to begin with? Due to diffraction?
Sharpness, yes, that can be enhanced, but I think it's quite lazy to confuse sharpness and resolution in a thread purporting to be dealing with shooting at tiny apertures.
The segue into processing techniques was interesting, if not on topic-
but the continued rubbishing of those who choose to believe the evidence of their own eyes, rather than counting scanned pixels, is just too much.
sanking
25-Jan-2011, 15:35
Sandy,
Where's the workshop?
Armando
Armando,
This is a one-on-one at my home in Easley, SC.
However, I am going to be doing a digital negative demo one day, and a carbon transfer demo the next, for the New England Large Format Group in April. Attendance is probably limited to members but you could check with Steve Sherman to make sure. steve@steve-sherman.com
Sandy
Lenny Eiger
25-Jan-2011, 15:52
I'm pretty confident that remark is directed at myself, and those who commented that the image posted was pretty fuzzy.
This comment was not directed at you.
Lenny, you've claimed 300MP resolution for the file you posted-
then subsequently claimed that resolution was unimportant.
The terms 'Sharpness' and 'Resolution' have been used interchangeably since this thread segued into a discussion about film and digital processing.*
When some people challenged your claims about the detail picture you posted,
you reacted in a childish and rude manner, indulged in personal slur, and requested that the thread be deleted.
It seems as if actual resolution is no more than a belief system around here,
and unsubstantiated claims are defended by rubbishing those who choose to disagree.
What I said was that I was not going to worry about f64 anymore. I got jumped on because it went against everyone's beliefs about diffraction and how important it is to shoot with less dof than I like to. The file I posted could have had more explanations about it or I could have done something else with it, it was a quick snapshot and apparently not enough.
I did not state that all lenses were perfect at all fstops. I did my own test and I got my results. No one was asking a question. What I got was all sorts of people telling me I should learn about swings and tilts, that I should go back and read up about diffraction, choose different developers and talk to other experts.
This whole area is a belief system, and relies on acts of faith, and the rebuttal of the laws of the universe, the casting out of non believers, and the impugning of their experience.
And those folks talking incessantly about resolution can't grasp that it is only a part of the picture. You want to test resolutions, sharpness, accutances, calculate exact megapixels and all that, go ahead. Me, I'm tested out... I want to go photograph.
The segue into processing techniques was interesting, if not on topic-
but the continued rubbishing of those who choose to believe the evidence of their own eyes, rather than counting scanned pixels, is just too much.
That's what I was doing, looking with my own eyes. At my own film developed in my own darkroom.
Ken Lee
25-Jan-2011, 16:14
"What I said was that I was not going to worry about f64 anymore".
Why bother to post it ?
Lenny Eiger
25-Jan-2011, 16:17
"What I said was that I was not going to worry about f64 anymore".
Why bother to post it ?
Why bother posting anything?
Ken Lee
25-Jan-2011, 17:01
"Why bother posting anything?"
Good point. :)
We're all here to share, and stirring things up now and then is part of the fun. We learn from it all.
onnect17
25-Jan-2011, 19:17
"Why bother posting anything?"
Good point. :)
We're all here to share, and stirring things up now and then is part of the fun. We learn from it all.
Visiting the moon, who cares!
Spending 10 years of research to get there, priceless!
Somebody is happy with f/64, ?
Discussion about all possible sources of softness in the image, priceless!
Just kidding, Lenny :D
onnect17
25-Jan-2011, 19:45
Armando,
This is a one-on-one at my home in Easley, SC.
However, I am going to be doing a digital negative demo one day, and a carbon transfer demo the next, for the New England Large Format Group in April. Attendance is probably limited to members but you could check with Steve Sherman to make sure. steve@steve-sherman.com
Sandy
Thanks Sandy. I will check with Steve.
rdenney
25-Jan-2011, 21:44
I use to use Microdol-X at 1:3 with Pan-X -- seemed to give me a nice compromise between fine grain and acutance.
Back in the deeps of time, I was using Rodinal with Panatomic-X. I figured the film gave me fine grain, and the developer gave me high acutance by not attempting to dissolve the grain. Also a good compromise. That was with small format and I rarely printed larger than 8x10. Pan-X gave me 11x14, but not bigger.
For many years, the biggest I can print has been 16x20. If I wanted to see grain for 4x5, I would just about have to soak a negative in battery acid after the developer.
On topic (to protect myself from the On-Topic Police), I always figured that depth of field is a creative decision, while diffraction is a resulting fact of life. The aperture I choose achieves the look I want, and a big part of that look is depth of field (or lack of it). If I end up with too much diffraction, I'll just print smaller. The alternative is a picture that can't be made at all.
I looked at Lenny's on-screen sample from three times minimum viewing distance, with the idea that my 100-ppi monitor has one third the resolution as a 300-ppi print. From three times minimum viewing distance, it looked quite sharp with considerable micro-detail. Any diffraction present would not have limited print size all that much, it seems to me. If printing optically on materials capable of much higher resolution, then it might be a bigger issue--I do get the notion that even when detail is greater than what we can see, it does have an effect on how the image looks to us. But that seems to me quite a subtlety compared to whether a picture is possible because it has enough depth of field, or impossible because it doesn't.
Rick "who has several photos that are limited in enlargeability but that are still valid photos that fulfilled their previsualization" Denney
Drew Wiley
25-Jan-2011, 22:12
I find myself shooting at f/64 rather frequently, at least on 8X10 film, but those kind
of shots probably won't get enlarged past 16x20, or possibly 20X24. I'm a lot pickier
with chromes or negs for 30X40 work, which I like sharp, sharp, sharp. When I want conspicuous grain and the nuance of selective focus etc, I hand-shoot a Nikon with high-speed film, and print very small. Love doing both, but very different strategies in each case. But with portraiture, which I do less often, I break all my own rules.
One can argue ad infinitum about fancy scans on fancy scanners. For an idiot like me scanning 5x7 negatives at 800spi or making contact prints, f64 is not a problem. You need a small aperture to get enough dof sometimes, and it has taken me more than a year to work it out.
Two examples attached scanned at 800spi. Shanghai 100 in Pyrocat M. I used the fp4 reciprocity chart and ended up with 2 to 3 1/2 minute exposures. Identical window light. 210mm Sironar S. Theese are at 1:1. No sharpening. Used a dof calculator to work out that I only had 5cm of dof to work with, even at f64.
Lenny Eiger
26-Jan-2011, 15:40
Lenny, so how big would you feel comfortable printing using f64 and your 8x10? I know you have tough standards, so where is your comfort zone?
Van,
26,660 pixels divided by 360 is 74 inches. I like to have a little more for b&w, around 450 or so (about 60 inches), so I would probably go to a 4000 ppi scan if I wanted a larger print. The most I've ever printed for my own work is 32x40. However, I've printed for others at 20 feet many times.
I may be answering a different question than the one you're asking. However, at the risk of starting this argument all over again (Please, No!) I've already said that I am happy with the sharpness I am seeing. Once its there in the scan, with sufficient pixels, it doesn't fall apart...
Lenny
Brian K
27-Jan-2011, 07:49
One can argue ad infinitum about fancy scans on fancy scanners. For an idiot like me scanning 5x7 negatives at 800spi or making contact prints, f64 is not a problem. You need a small aperture to get enough dof sometimes, and it has taken me more than a year to work it out.
Two examples attached scanned at 800spi. Shanghai 100 in Pyrocat M. I used the fp4 reciprocity chart and ended up with 2 to 3 1/2 minute exposures. Identical window light. 210mm Sironar S. Theese are at 1:1. No sharpening. Used a dof calculator to work out that I only had 5cm of dof to work with, even at f64.
MDM what is the point of these sample images? They're both soft in focus. Nothing really looks in focus. And BTW the 210mm Sironar-S, which I also happen to own, is not good at 1:1, it's only decent at that aperture. So using f64 with the Sironar-s at 1:1 is already a compromise in image quality.
If you're committed to doing this type of work then you should consider a dedicated macro lens or a process lens like an Apo Ronar.
Lenny Eiger
27-Jan-2011, 10:16
The math part I already knew, but you did answer my question when you said it doesn't fall apart at those larger prints sizes (60 inches +). In other words, more then good enough for close inspection, even though f/22 might be a bit better, but without a side by side comparison it becomes irrelevant.
My thought about this is that the key is to examine the whole system. Identify what's important and where the bottlenecks are. Consider how many folks are using the 750's to get a scan and how satisfied they are. Next to a drum scan they are very blurry.... What it is the effect of opening up to f22 to get things sharp that tiny bit sharper and then using a blurry scanner? I say there is a bottleneck there - at least vs a drum scanner.
Similarly, there is another one at the printing stage. There are only so many dots that these inkjets can put out onto the paper. When you consider that colors have to mix on the way down from the head to the paper (in about an 1/8 of an inch or less) it becomes apparent why the system has a sharpness limit. It's pretty terrific, in my mind, but it isn't perfection. There are other systems that are sharper, but they don't have as full a color space an inkjet does.
I don't think my printer, at its highest resolution, can substantially distinguish between f22 and f45, even in b&w. I have seen the difference, but it is so subtle as to disappear in the context of the image, or in my mind... That's my system, not yours or anyone else's, of course...
Lenny
Edwin Beckenbach
27-Jan-2011, 10:31
Maybe at 4x or 5x, but if you can't distinguish the difference between f22 and f45 at a 10x enlargement then there is something wrong with your system.
My thought about this is that the key is to examine the whole system. Identify what's important and where the bottlenecks are. Consider how many folks are using the 750's to get a scan and how satisfied they are. Next to a drum scan they are very blurry.... What it is the effect of opening up to f22 to get things sharp that tiny bit sharper and then using a blurry scanner? I say there is a bottleneck there - at least vs a drum scanner.
Similarly, there is another one at the printing stage. There are only so many dots that these inkjets can put out onto the paper. When you consider that colors have to mix on the way down from the head to the paper (in about an 1/8 of an inch or less) it becomes apparent why the system has a sharpness limit. It's pretty terrific, in my mind, but it isn't perfection. There are other systems that are sharper, but they don't have as full a color space an inkjet does.
I don't think my printer, at its highest resolution, can substantially distinguish between f22 and f45, even in b&w. I have seen the difference, but it is so subtle as to disappear in the context of the image, or in my mind... That's my system, not yours or anyone else's, of course...
Lenny
Lenny Eiger
27-Jan-2011, 10:34
Maybe at 4x or 5x, but if you can't distinguish the difference between f22 and f45 at a 10x enlargement then there is something wrong with your system.
I don't need to do 10x enlargements.
Edwin Beckenbach
27-Jan-2011, 10:37
So why do you talk about printing 8x10 at f64 up to 74 inches?
I don't need to do 10x enlargements.
Lenny Eiger
27-Jan-2011, 10:48
So why do you talk about printing 8x10 at f64 up to 74 inches?
If you read the post, you would have seen that my max is 32x40, which is a fairly small enlargement.
I wrote that last post because someone asked me a question and I answered it the way I see it. I didn't say I can't see the difference, I said the difference does not necessarily make it thru the rest of the process and it isn't meaningful to me. You don't have to agree with me, and you know nothing about my system or its capacities.
I'm sick and tired of answering people with your tone, and I'm going to stop. Hidden behind every comment from people who disagree, or don't have the lens I do, or some other part of the equation, is the insult that I'm some kind of idiot or I don't know what I'm doing. I have done my work. I don't mind disagreement at all. However, disrespect is only going to break this community apart and all the people who are expert at something will leave.
Van - if you want to talk further about this issue and mutual experiences, one way or the other, I'm happy to, give me a call... and let's take this off the list....
Lenny
Edwin Beckenbach
27-Jan-2011, 10:52
Sorry. BTW at 32x40 from 8x10 I completely agree with your conclusions.
If you read the post, you would have seen that my max is 32x40, which is a fairly small enlargement.
I wrote that last post because someone asked me a question and I answered it the way I see it. I didn't say I can't see the difference, I said the difference does not necessarily make it thru the rest of the process and it isn't meaningful to me. You don't have to agree with me, and you know nothing about my system or its capacities.
I'm sick and tired of answering people with your tone, and I'm going to stop. Hidden behind every comment from people who disagree, or don't have the lens I do, or some other part of the equation, is the insult that I'm some kind of idiot or I don't know what I'm doing. I have done my work. I don't mind disagreement at all. However, disrespect is only going to break this community apart and all the people who are expert at something will leave.
Van - if you want to talk further about this issue and mutual experiences, one way or the other, I'm happy to, give me a call... and let's take this off the list....
Lenny
MDM what is the point of these sample images? They're both soft in focus. Nothing really looks in focus. And BTW the 210mm Sironar-S, which I also happen to own, is not good at 1:1, it's only decent at that aperture. So using f64 with the Sironar-s at 1:1 is already a compromise in image quality.
If you're committed to doing this type of work then you should consider a dedicated macro lens or a process lens like an Apo Ronar.
They are pretty enough to contact print and will print on an A4 sheet nicely. 1:1 = pixel for pixel. Both would just about be in the recomended range for a sironar s, 1:5 or 5:1 which ever it is because I can never remember. I have a 240mm ronar but in dim window light focusing at f9 is no fun. A sharp macro lens would be nice but I cant justify one, even at a low price. If they are out of focus then I have no where to hide, but a long exposure makes movement a more likely culprit. I am happy, I will contact print them and they bring me a step closer to where I want to be. 99% of people would seldom print bigger than a4 or letter or 8x10, if at all.
Really, I dont buy into the compulsive perfectionism, regardless of cost, that happens here sometimes. If a fancy pants printer is happy with f64, who am I to argue. In fact I agree.
sanking
27-Jan-2011, 13:10
Just thinking out loud here. If you are shooting at f/64, which might be necessary in some situationswith 8X10 to get adequate DOF, you will be getting a maximum resolution of about 40 lp/mm from the effects of diffraction. I am sure Lenny knows this so I am definitely not trying to insult him.
However, it might just be that Lenny could put that Aztek Premier away and scan these B&W negatives with an Epson V700/V750. These scanners will give more than 40 lp/mm effective resolution, and with a well exposed B&W negative you really don't need a lot of dynamic range.
I would personally bet that there would be very little difference, if any, in image quality between a negative exposed at f/64 and scanned with an Epson V700 and one exposed the same way and scanned with a Premier. I assume expert post-scan processing in both cases. In this case I believe the weak leak in the chain of image quality would be the diffraction limited exposure, not the scanner.
I for one do not agree with the opinion expressed earlier in this thread that DOF always trumps sharpness for aesthetic purposes. There are many situations where images live or die on their sharpness.
Sandy King
Edwin Beckenbach
27-Jan-2011, 13:27
Unless I'm mistaken, closer to 20 lp/mm than 40 lp/mm.
Just thinking out loud here. If you are shooting at f/64, which might be necessary in some situationswith 8X10 to get adequate DOF, you will be getting a maximum resolution of about 40 lp/mm from the effects of diffraction. I am sure Lenny knows this so I am definitely not trying to insult him.
sanking
27-Jan-2011, 13:56
Unless I'm mistaken, closer to 20 lp/mm than 40 lp/mm.
Edwin,
I use the formula 1800 / f/stop to estimate diffraction limited resolution. That comes to 28 lp/mm for f/64, which is indeed closer to 20 lp/mm than my figure of 40 lp/mm.
That allows approximately a 2X magnification to stay within the limits of the threshold of human resolution when viewing a print at ten to fifteen inches from the eye.
Sandy
Edwin Beckenbach
27-Jan-2011, 14:12
Agreed. I use 1500/ f which is slightly more conservative. Regardless, I can't see any good reason for scanning f64 beyond 1200 or 1500 dpi (2x the image resolution) because there isn't any more image to resolve. I get visible softness in 16x20 enlargements from 4x5 at f64, quite acceptable in my opinion but also clearly noticeable.
Edwin,
I use the formula 1800 / f/stop to estimate diffraction limited resolution. That comes to 28 lp/mm for f/64, which is indeed closer to 20 lp/mm than my figure of 40 lp/mm.
That allows approximately a 2X magnification to stay within the limits of the threshold of human resolution when viewing a print at ten to fifteen inches from the eye.
Sandy
rdenney
27-Jan-2011, 14:20
I for one do not agree with the opinion expressed earlier in this thread that DOF always trumps sharpness for aesthetic purposes. There are many situations where images live or die on their sharpness.
I agree. I was making a distinction, however, based on image feasibility. If I visualize an image such that it would live or die on its sharpness, and if it was true in that case that the aperture I needed to provide vizualized depth of field was too small to support that sharpness, then I would have to conclude that my vizualization was infeasible. I may have to choose between my visualization and my desired print size. My usual choice is to use the smaller aperture and limit print size.
Rick "agreeing with the weakest link analysis but suggesting that one way to address a weak link is to lighten the load" Denney
...
However, it might just be that Lenny could put that Aztek Premier away and scan these B&W negatives with an Epson V700/V750. These scanners will give more than 40 lp/mm effective resolution, and with a well exposed B&W negative you really don't need a lot of dynamic range.
I would personally bet that there would be very little difference, if any, in image quality between a negative exposed at f/64 and scanned with an Epson V700 and one exposed the same way and scanned with a Premier. ...
There is a lot more to scanning than resolution or sharpness. A LOT MORE. In fact I learned this in part from experience and in part by reading Lenny's writings about this on this and other discussion boards.
I would actually be willing to bet that the drum scan would be much sharper and would require much less software sharpening. And the tonality, especially the separation of mid tones, will be far superior on the drum scanner.
I've noticed this when comparing my drum scans to my Epson scans. And I have a lowly Howtek HR8000, not a fancy-pants Aztek.
I often shoot my 4x5 lenses at f/32. And I print 40x50. Are the results as sharp as when I shoot at f/22 or f/16? No of course not, it would contradict the science. But are the photos better because everything I wanted in focus was in focus and there are no distracting soft areas in the background or foreground? Of course.
Careful Sandy, thinking, in this thread, represents unorthodoxy, and will only invite derision,scorn, and tantrums. I'd reckon 28 lp/mm might represent the very best result possible for f/64, and other factors might conspire to lessen that number. It's possible that a V750, far from being a bottleneck, in this case, could be up to two times overkill.
64.8 mp, as I mentioned earlier in this thread, and that's being generous.
I'm glad some sense is finally being talked in this thread-
It's lonely being a non believer-
Uniform sharpness is a valid ambition for a picture, but at the sizes mentioned, it might end up being uniform unsharpness.
Which is fine too, if that's what you want-
sanking
27-Jan-2011, 14:50
There is a lot more to scanning than resolution or sharpness. A LOT MORE. In fact I learned this in part from experience and in part by reading Lenny's writings about this on this and other discussion boards.
I would actually be willing to bet that the drum scan would be much sharper and would require much less software sharpening. And the tonality, especially the separation of mid tones, will be far superior on the drum scanner.
I have a real good idea what scanning is, and the fact of the matter is that there are times when you won't get better image quality with a drum scan than with a lowly Epson V700/V750. Of course there is more to scanning than resolution, but resolution and dynamic range are very important based on my own comparisons, which involves scans with several different drum scanners and several different CCD type scanners. And my conclusion is that if one insists that a drum scanner will always give better final image quality at a given print size, regardless of the characteristics of the negative and scanning parameters, then I am not going to hesitate to remark that the emperor is walking through town naked, because in my opinion that is nothing but BS. It is simply ludicrous to insist that you always need a drum scan for optimum print quality. You don't, and that is a fact.
Sandy King
Greg Miller
27-Jan-2011, 14:51
There is a lot more to scanning than resolution or sharpness. A LOT MORE. In fact I learned this in part from experience and in part by reading Lenny's writings about this on this and other discussion boards.
I would actually be willing to bet that the drum scan would be much sharper and would require much less software sharpening. And the tonality, especially the separation of mid tones, will be far superior on the drum scanner.
I think the drum scan would also have significantly better shadow detail. And less color fringing too.
sanking
27-Jan-2011, 14:58
I think the drum scan would also have significantly better shadow detail. And less color fringing too.
Although Lenny did not specifically state this at the beginning of this thread I am fairly certain that he was talking about B&W film, so color fringing would not be an issue. And assuming the B&W negative was not over-exposed or over-developed, which I doubt Lenny would do either, I have my doubts that a drum scanner would give better shadow detail than a V700/V750.
Sandy
Kirk Gittings
27-Jan-2011, 15:08
I would actually be willing to bet that the drum scan would be much sharper and would require much less software sharpening. And the tonality, especially the separation of mid tones, will be far superior on the drum scanner.
This may sound like mumbo jumbo, but.........here goes. I've been using an Epson 750 since they first came out and Imacons for over ten years. I think I am pretty good with them. Now I manipulate the tones in my b&w images allot-I like allot of drama in my prints. Anyway, I have noticed that with good drum scans (I haven't tried them all, but Lenny's are the best I have ever gotten) that I can achieve the look I am after with far less work and more importantly with less artifacts. An example is the enhanced noise at transitions between tones when you darken what were blue skies allot-you get the noise at the edge of the lighter tones along the horizon. With a good drum scan I can get much better transitions than with either the Epson or the Imacons-I've seen this with Imacon scans from pro operators too. That increased separation Noah mentioned above means something real in my world.
There is an image I am working on right now that I first scanned on the Epson 750, then I scanned it on an Imacon, then I had it scanned by an Imacon pro at a lab and finally I sent it to Lenny to be scanned and finally then it processed like a dream. Now maybe this is just my weird workflow-how hard I push the tones. But to me the drum scan magic is real.
Greg Miller
27-Jan-2011, 15:09
Although Lenny did not specifically state this at the beginning of this thread I am fairly certain that he was talking about B&W film, so color fringing would not be an issue. And assuming the B&W negative was not over-exposed or over-developed, which I doubt Lenny would do either, I have my doubts that a drum scanner would give better shadow detail than a V700/V750.
Sandy
I will disagree about the shadow detail. If there is detail in deep shadows, a drum scanner will pull it out better. In fact, the only photo in my first book that was rejected by my publisher was a 4x5 transparency that had been scanned, by an Epson, that could not pull out enough properly exposed shadow detail (there were shadows (not particularly deep) and the shadows had detail). That photo was re-scanned by a drum scanner (and did not require any significant or abnormal processing - meaning that the scanned image and transparency looked quite similar).
And did you shoot that at f/64?
Kirk Gittings
27-Jan-2011, 15:14
I will disagree about the shadow detail. If there is detail in deep shadows, a drum scanner will pull it out better. In fact, the only photo in my first book that was rejected by my publisher was a 4x5 transparency that had been scanned, by an Epson, that could not pull out enough properly exposed shadow detail (there were shadows (not particularly deep) and the shadows had detail). That photo was re-scanned by a drum scanner (and did not require any significant or abnormal processing - meaning that the scanned image and transparency looked quite similar).
I have had this experience too with both b&w and color.
sanking
27-Jan-2011, 15:18
I will disagree about the shadow detail. If there is detail in deep shadows, a drum scanner will pull it out better. In fact, the only photo in my first book that was rejected by my publisher was a 4x5 transparency that had been scanned, by an Epson, that could not pull out enough properly exposed shadow detail (there were shadows (not particularly deep) and the shadows had detail). That photo was re-scanned by a drum scanner (and did not require any significant or abnormal processing - meaning that the scanned image and transparency looked quite similar).
Greg,
I believe you are a color photographer, right? Then your comment is not relevant to my remarks because I specifically limited what I said to B&W negatives, and I am fairly certain that this entire thread has been about a B&W negative that Lenny exposed. Of course any one with half a brain knows that if you want to pull all of the shadow detail from a color transparency you need a drum scan. But you don't need a drum scan to do with with well exposed and developed B&W film.
I wonder sometimes if people even read what others write or if they don't just bit back like angry dogs.
Sandy
Kirk Gittings
27-Jan-2011, 15:25
Sandy, I have had this experience with b&w negatives, but always with underexposed b&w negatives.
sanking
27-Jan-2011, 15:44
Sandy, I have had this experience with b&w negatives, but always with underexposed b&w negatives.
Well, that would explain why I have never seen this problem. All of my b&w negatives are perfectly exposed and perfectly developed. :D
Sandy
Greg Miller
27-Jan-2011, 16:00
Greg,
I believe you are a color photographer, right? Then your comment is not relevant to my remarks because I specifically limited what I said to B&W negatives, and I am fairly certain that this entire thread has been about a B&W negative that Lenny exposed. Of course any one with half a brain knows that if you want to pull all of the shadow detail from a color transparency you need a drum scan. But you don't need a drum scan to do with with well exposed and developed B&W film.
I wonder sometimes if people even read what others write or if they don't just bit back like angry dogs.
Sandy
Well, I don't think I bit back like an angry dog; I just added a couple of comments that contained no vitriol. But now I feel like one is biting me back.
I have read this thread pretty carefully from the start. It started out as a comment about f64 sharpness, which I do not believe has anything to do with B&W or color. Then the thread drifted into drum scanning vs. flatbed scanning. I'll bet I'm not the only one who missed the fact that this conversation was limited to B&W. I guess I'll go back to lurking an not offering any thoughts from my own personal experience.
sanking
27-Jan-2011, 16:17
I have read this thread pretty carefully from the start. It started out as a comment about f64 sharpness, which I do not believe has anything to do with B&W or color. Then the thread drifted into drum scanning vs. flatbed scanning. I'll bet I'm not the only one who missed the fact that this conversation was limited to B&W. I guess I'll go back to lurking an not offering any thoughts from my own personal experience.
Greg,
I apologize for my comment. I mistakenly personalized it when in fact it was a reaction to other comments as well as your own.
In any event my comparison of drum scanners and Epson flatbeds was limited to B&W film, whether that was fully explained or not.
Sandy
alharding
27-Jan-2011, 16:38
F64 does increase depth of field and generally makes a sharp image throughout but be wary of reciprocity failure on longer exposures, which can make a sharp image appear out of focus.
Drew Wiley
27-Jan-2011, 16:46
Reciprocity failure has nothing to do with focus. At very long exposures a number of
films will require adjustment in development to compensate for contrast issues, or with
some pan films, the bias of the spectral sensitivity can distinctly shift, so require some
kind of exposure and development correction in its own right. Or a long exposure might
simply give more opportunity for a breeze to arise and shake either the subject or the
camera. Is this what you mean?
I'm a color shooter too--though diffraction doesn't care what kind of film is in the camera. I've scanned plenty of B&W negs over the years.
When I scan my goal is to translate as much of the information in the negative as possible to the final print. So it doesn't matter if the negative is totally soft. A good scan of a soft neg, to me, would be one that resolves the grain (or dye clouds) and captures as much of the tonal range as possible. The scanner is just a way to transfer as much information as possible from the negative to the printer.
I print at sizes where grain is visible. A scan that sharply resolves the film grain actually makes the whole print look sharper.
Greg Miller
27-Jan-2011, 17:09
Greg,
I apologize for my comment. I mistakenly personalized it when in fact it was a reaction to other comments as well as your own.
In any event my comparison of drum scanners and Epson flatbeds was limited to B&W film, whether that was fully explained or not.
Sandy
No problem. My first comment would have better understood if I was specific that I was talking about shadow detail in a transparency (not a negative).
I am curious, sincerely and politely, what your reaction would have been if I had said "highlight detail in a negative" (similar concept as with shadow detail in a positive). My own assumption would be that a drum scanner would pull more detail than a flat bed. I would also assume that color would fare slightly better than B&W because there are 3 channels to help differentiate neighboring pixels rather than one. But I could be wrong.
sanking
27-Jan-2011, 17:38
I am curious, sincerely and politely, what your reaction would have been if I had said "highlight detail in a negative" (similar concept as with shadow detail in a positive). My own assumption would be that a drum scanner would pull more detail than a flat bed. I would also assume that color would fare slightly better than B&W because there are 3 channels to help differentiate neighboring pixels rather than one. But I could be wrong.
Well, I want to be clear that my only case for an Epson flatbed was made only with reference to a B&W negative that was exposed at an aperture that gives fairly low resolution in lp/mm, with the farther assumption that the negative was well exposed, and not over developed. If that is the case there should be no problem at all in pulling detail from the highlights. And I believe that would be true of color negatives that are well exposed as well.
Now, if the negative is either over exposed or developed too long that changes the game entirely, and it might well be that an Epson flatbed would not be capable of capturing all of the highlight detail.
I don't accept at all the statement that drum scanners give better tonal rendition with well exposed and developed b&w negative. They may depending on the skill of the operator, but then again they may not. When it comes to scanning artifacts you can get a lot of these with either drum or CCD scanners if the machine is not in good working condition.
Sandy
Lenny Eiger
27-Jan-2011, 17:52
I don't accept at all the statement that drum scanners give better tonal rendition with well exposed and developed b&w negative.
Sandy
Sandy, This has simply not been my experience. I've seen many 750 scans and compared my drum with lots of types of ccd's. The drum has won every time in tonal rendition, and for that matter, in color sensitivity.
As far as resolution goes, I have been surprised by what I see. It doesn't match the numbers but it also wasn't done with an air force target. It may not be sensible, as jbl stated, but it's in right here in my hand. FWIW, it is far more than what a 750 is capable of. I understand that I have no business making my case unless I can prove it properly. Next set of shots I do I'll do a proper comparison and see if I can't put it together in a way that actually makes sense, one way or the other...
Lenny
P.S. In the meantime, let's be nicer to each other. Not pointing at anyone, but at all of us... We all know something, we can all be wrong about something we always thought was right... we can all come to a wrong conclusion about something we see.
sanking
27-Jan-2011, 19:02
I understand that I have no business making my case unless I can prove it properly. Next set of shots I do I'll do a proper comparison and see if I can't put it together in a way that actually makes sense, one way or the other...
Lenny
Good point. Some of us do remember when you were bad mouthing TMY and other T grain films as inferior to traditional emulsion films when in fact you had never thoroughly compared them. Fast forward a few years and lo and behold you have decided that the two best films for your work at Delta 100 and TMY-2, both T grain emulsion films.
Some of us also remember that you were on the LF forum trashing Eversmart scanners, when in fact your opinions were based not on personal comparison but on comparison made by folks at Aztek, who have a vested interest in trashing the competition.
Now, for what it is worth I do understand what drums scanners can do and in many cases they are essential to get the most out of a negative or transparency. However, in the end the scanner is one of several tools that enter into the work flow of someone who develops film to scan, and there is a point at which it does not make one bit of difference what kind of scanner you use because the other links in the chain are more important to final image quality than the scan itself. You can compare the most expensive modern Schneider SSXL lens in the world with a 19th century rapid rectilinear on your 8X10, but if the wind is blowing the camera around like mad and you shoot at a very slow shutter speed you will get a big blur with both lenses.
Sandy
Lenny Eiger
27-Jan-2011, 20:17
Good point. Some of us do remember when you were bad mouthing TMY and other T grain films as inferior to traditional emulsion films when in fact you had never thoroughly compared them.
Sandy, this is unfair. First of all, it's old history. Second I went through a very large number of boxes of film, tested tons of developers, even made up some of my own, talked to Bill Wilson, Gordon Hutchins and Steve Anchell, all of whom told me what I eventually repeated, before I finally found the problem. I have also been very clear that I was wrong about that.
Since then, I have been very careful to qualify what I say, using words like "I think" this is the way it is vs "I know" or this works for me and suggesting people do their own testing.
Some of us also remember that you were on the LF forum trashing Eversmart scanners, when in fact your opinions were based not on personal comparison but on comparison made by folks at Aztek, who have a vested interest in trashing the competition.
This is not true, either. I have an associate locally who has an Eversmart who made a scan for me that was quite unacceptable. I also have good reason to believe what Phil Lippincott told me. Every time he said something I thought was outrageous I would go away and test it out and behold, he was right. When Phil met me he took a liking to me, he treated me like another son. He appreciated my work, and there are two of my prints hanging up at the Aztek office. I had already bought my scanner and he taught me how to use it, explained many of the technical intricacies. He had no reason to lie to me.
While I might chalk up the Eversmart scan I received up to a lack of operator expertise, there is a huge difference between a CCD and a PMT. That's physics. The differences between Aztek's independent analysis of the Eversmart and what some people want to suggest about it is not small. It was a reasonable conclusion. I have not had the opportunity to see something great from an Eversmart as yet. However, I have seen things that surprised me from just about every scanner.
We could look into your lab, and every single person here, and we could find places where you are absolutely sure of something, which is incorrect. None of us has all the answers. That's life.
You say "Good point" like it was going to be polite, but then it isn't. We already had this conversation on the telephone, and if you recall I expressed remorse at having expressed the opinions about the film. If you want to tell someone that their behavior is less than perfect (especially someone you have direct access to) it is not very nice to do so in a public forum. Its an unnecessary, direct and public attack on someone's character. In our phone conversations, I offered you my friendship and I invited you to my home. Maybe you feel good taking putting someone else down in public. But it doesn't feel good over here. It feels like I've lost a friend, maybe one I never had.
Everyone should always make up their own mind. I don't want anyone to "follow" me - or agree with me - about anything. Except that maybe civility is a better way to do this.
Lenny
onnect17
27-Jan-2011, 21:30
I hope I can help the conversation with my opinion.
The level of noise in the howtek is a lot higher than the Epson. Period. The perception of better details in the shadows is only because this devices features a two path stage amplifier before the A/D conversion: linear and logarithm. Add to the equation the small apperture used for a decent focus and the amount of photons reaching the PMTs is minimal.
Regarding the F/64 resolution I agree with Sandy. Based on my numbers, the wall in optical resolution in this case (assuming 580nm yellow) is the equivalent to around 561 dpi. You can scan the negatives at a million dpi if you want, still the information is not there. Check the "size of smallest object that the lens can resolve" paragragraph in http://en.wikipedia.org/wiki/Rayleigh_criterion#Explanation
1.22 * 0.00000058 * 64 = 0.00004529
To dpi --> 25.4mm / 0.000045.29 = 561
sanking
27-Jan-2011, 21:38
Lenny,
All I can say is that if you felt so strongly about this why did you not just pick up the phone and tell me off privately instead of making me look like sh&t in public.
I don't have any more words for this. It is late and I must let it go, otherwise I will brood about it for hours.
Sandy
Peter De Smidt
27-Jan-2011, 21:47
Recently, I've been scanning some of my old 35mm film with my Cezanne scanner. Some if it is on Kodak HIE film, which was very grainy film. I did comparison scans at 2000, 3000, 4000, 5000, and 6000 dpi. I sincerely doubt that any of the scans left out scene detail, since the film's grain was so coarse, and I doubted that there would be any benefit with the higher res scans, but there was! As the res got higher, the grain became much less obtrusive, and the 6000 dpi scan was clearly the best. (The Seybold report claimed the Cezanne's real resolution topped out near 6000 dpi.) I've since had another experienced Cezanne user verify this result. Thus in this case the resolution of the taking lens/film/processing combination did not determine the best scanning resolution, and I expect that a superior scanner, such as the one Lenny uses, might've produced an even better file, even with the low res film.
Kirk Gittings
27-Jan-2011, 22:18
The level of noise in the howtek is a lot higher than the Epson. Period.
If I understand your point. I think my experience is the exact oposite. Not that I have ever operated a Howtek, but with the scans I have had made-the Howtek has dramatically less noise than the Epson. Even with the multipass noise reducing thing-a-ma-jig in Silverfast. The noise in the shadows of epson b&w scans are significant compared to the Howtek where noise seems non-existent. What am I missing here? What am I not understanding?
onnect17
27-Jan-2011, 23:00
Kirk,
As Sandy said, a lot depends how familiar with the hardware and software the person doing the scan is. The more familiar the operator gets with the features and shortcomings of the system the better.
The amount of energy reaching the sensor in the CCD based scanners like the Epson is a lot higher than the PMTs in the drum scanners so the analog noise is lower. That means scanning a single step of density let say 2.0 will show more noise in the drum compared to the CCD.
The typical flatbed CCD scanner will have a fixed logarithm applied to the output with 0.5 to 0.6 density allocated to the center of the histogram. So as you can imagine densities in the 3.0 order are being compressed at the end and in most cases this is done by the manufaturer using software in the driver to cut costs.
Now, in the typical drum scanner each color channel has his own circuit capable of calibrate max and min density, gamma, etc. in the analog stage, before the conversion to digital, and is expesive. In fact you can set the configuration to run a calibration at the begining of every scan.
Some old but high end CCD scanners like the LeafScan 45 were built with optics and hardware way better that any Imacon, just slower.
In short words. The noise you see in the Epson is probably related to digital manipulation vs the most likely analog nature in the drum scanners.
Kirk Gittings
28-Jan-2011, 09:59
In short words. The noise you see in the Epson is probably related to digital manipulation vs the most likely analog nature in the drum scanners.
What digital manipulation? You can see it in the shadows of a simple linear scan from an Epson? The noise in the deep shadows in scans from Epson scanners is well known (and other scanners at this level) and obvious to see. That is why Silverfast offers the multi-exposure sampling feature http://www.silverfast.com/highlights/multisampling/en.html What you are describing-that Epsons have less noise than Howteks-is contary to my experience. I'm sorry I don't get it. Even less so comparing Epson scans to an Aztec Premier.
Also, FWIW I have a fair amount of experience scanning. I have done my own scanning on Epsons for many hundreds of my color images for magazine articles, and probably a couple hundred on Imacons of my b&w images that have appeared in museum shows additionally I have scanned and printed a show of my sister-in-laws at the Smithsonian and I teach scanning on Epsons and Imacons as part of my classes at SAIC. If nothing else I am a pretty knowledgeable and demanding consumer of scans and know when I am getting a decent scan from myself or a drum scan operator.
onnect17
28-Jan-2011, 12:15
Kirk,
Digital manipulation does not imply is done by the operator. Could be done, as in this case, by the driver or the firmware and the manufactures will not tell you about it.
When I say linear I'm not referring to a curve in the screen, I'm talking about the output signal in the CCD before quantization and AFAIK the user do not have access to it in any Epson model, not even RAW data.
Multiexposure and multisampling are two different things. Silverfast is making money selling multiples scans or exposures as multisampling. The name is clear, takes multiple continuous samples and decide using average or any other criteria which is the final value of the pixel (Nikon coolscan uses it).
Multiexposure involves another scan introducing mechanical error and affecting resolution.
Another way to improve the SNR is control the power of the light source (analog gain in Nikonscan) or extend the duration of sampling (Adaptive light in FlexColor)
Manufacturers are in the business of making money and processing data by software is a lot cheaper and flexible than by hardware and 99% of the users do not see the difference in the product. A typical example are the digital cameras. Saving in optics and a lot of post processing.
I owned and own several scanners. Clicking behind a keyboard is not enough for me. I have to open it, see what's inside, understand the working principle, analyze the output and all have pros and cons, in hardware and software.
Glad to hear you teach the subject and I'm sure your students love the class. A simple and interesting task (if you are not doing it already) could be to scan a step wedge as a positive without any correction in two scanners using different technologies and discuss the results.
Don Hutton
28-Jan-2011, 12:38
I hope I can help the conversation with my opinion.
The level of noise in the howtek is a lot higher than the Epson. Period.If that's the case, it's due to the Howtek operator setting the aperture inappropriately for the film which is resulting in extensive grain aliasing coupled with the fact that the Epson's lack of extreme sharpness (probably the result of very economical optics combined with fairy crude stepping mechanics) causes a smoothing blur to the finest of details (i.e. anything beyond the actual optical resolution of the Epson in question). At comparable optical resolution, the Howtek with a competent operator will produce a scan with less noise than an Epson flatbed. Once the "blurring" effect is reduced to a similar level of sharpness that the RAW output of the Howtek should be capable of, the Howtek scan will have obviously less noise.
onnect17
28-Jan-2011, 13:05
Don,
I'm not familiar with the RAW output in the howtek. I'm using DPL and tiff is the only option to me.
Don Hutton
28-Jan-2011, 13:42
Don,
I'm not familiar with the RAW output in the howtek. I'm using DPL and tiff is the only option to me.By RAW, I simply meant unsharpened, unmanipulated scan (make the scan with a film profile - and no sharpening).
onnect17
28-Jan-2011, 15:41
The film profiles (not color profiles) are curves which are downloaded into the 12 bits LUTs of the scanner and is not longer raw data.
Don Hutton
28-Jan-2011, 15:53
The film profiles (not color profiles) are curves which are downloaded into the 12 bits LUTs of the scanner and is not longer raw data.Fine - use a film profile and no sharpening - call it whatever you like - and you'll have a better result for a given optical resolution IF you have the aperture set appropriately AND your scanner is in good mechanical and electrical condition. More than half the drum scans I have seen from amateurs and professional operators have had the aperture set incorrectly (there's a tendency to stop it right down as small as possible - 6 microns on a 4500 - because operators don't appreciate the optical differences of "oversampling" a wider area). Some testing can reveal some very interesting facts about an optimal aperture for a given emulsion and subject matter. Evidence of testing seems to be lacking in a lot of the scans I've examined.
onnect17
28-Jan-2011, 16:35
I would say mine is OK usable condition, not better than that. I use the 13 microns setting because the amount of noise at 6 is just too much, at least in the D4000.
Also when I select a number above 13 the focus feels it. All this at 4000dpi with fresh, clean and aligned lamps using manual focus.
Never thought of taking the subject in consideration.
sanking
29-Jan-2011, 09:24
Peter,
Do you have any idea why the grain become less obtrusive as you scanned at higher resolution? And can you provide some details of the scan? Were you scanning in grayscale, and was it a dry or fluid mounted scan? And did you keep the scan at the scan resolution or down size before evaluating the grain.
Sandy
Recently, I've been scanning some of my old 35mm film with my Cezanne scanner. Some if it is on Kodak HIE film, which was very grainy film. I did comparison scans at 2000, 3000, 4000, 5000, and 6000 dpi. I sincerely doubt that any of the scans left out scene detail, since the film's grain was so coarse, and I doubted that there would be any benefit with the higher res scans, but there was! As the res got higher, the grain became much less obtrusive, and the 6000 dpi scan was clearly the best.
Peter De Smidt
29-Jan-2011, 10:15
Hi Sandy,
It might be due to grain aliasing, although I really don't know. I scanned "dry" using a clam shell holder. I scanned in 16-bit RGB as a positive, and I down-res'd the larger scans using Photoshop's bicubric interpolation to match the lowest one.
onnect17
29-Jan-2011, 21:04
Peter, I think it makes perfect sense. The higher the sampling frequency (in this case scanning resolution) the more accurate you will be able to capture the shape and size of the grain. In fact, with regular developers (no stain) the image structure should be almost monotone, pretty much the gelatin plus the grain. At 6000 dpi a gray surface in grainy negative should show an histogram with a couple of bars instead of one in the middle.
The worst scan resolution should be the closest to the grain size and once you are over twice the grain size the sampling error becomes smaller and smaller (check Nyquist frequency in wikipedia). It also explains why so many love TMY more than TMX.
onnect17
3-Feb-2011, 15:49
I remember reading about optimal focus and f-stop in VC magazine a couple of years back. Here's the link to the two parts article.
http://www-unix.oit.umass.edu/~rbhome/technical.htm
Sal Santamaura
5-Apr-2016, 10:19
This thread and its controversies has been dormant for quite a while. Lenny (the OP) doesn't even post here any more. But, I've some information to add, so here goes for the archive.
Back in post #1, Lenny described how he tested by "pointing his camera out his front door and closing down to f/64." He wrote that he was perfectly satisfied with the resulting sharpness. Lenny first used a 300mm f/5.6 Nikkor W for the experiment. Later, seeking more coverage and possibly better performance, he obtained a 300mm f/5.6 Apo Sironar S. Comparing the two lenses, Lenny found them to be almost identical. Not wanting or needing them both, he offered the Nikkor for sale. I bought it.
Fast forward to last week. Lots of life got in the way since my Nikkor W purchase occurred. However, now having the time (and three 3004 Expert drums), I finally got around to comparing eight of my lenses, including that 300mm Nikkor W, using the "standard scene" in our back yard. That scene includes an Edmunds chart, Macbeth Color Checker, Kodak gray card and lots of natural elements like trees and shrubs, all about 50 feet distant from the camera.
Tested lenses were:
450mm f/8 CM Fujinon W
450mm f/12.5 Fujinon C
420mm f/8 Fujinon L
300mm f/9 Fujinon A (EBC multi-coated version)
300mm f/5.6 Fujinon W (single-coated version)
300mm f/5.6 Nikkor W
270mm f/9 G-Claron
250mm f/6.7 Fujinon W
Two exposures, incorporating significant rise and shift, thereby using much of the available image circles, were made with each lens; one at f/45 and another at f/64. These were the results at f/45.
Long lenses: the 450CM-W and 420 L were fairly sharp. The 450 C was slightly less sharp.
"Normal" lenses: the 300 A was moderately sharp (less so than the 450 CM-W/C). The Fuji 300 W was significantly sharper than the 300 A. The Nikkor 300 W was extraordinarily sharp.
"Wide" lenses: the 270 G-Claron was very sharp (performance between the 300 A and Fuji 300 W). The 250 W was moderately sharp (about like the 300 A).
At f/64, seven of these lenses suffered substantial sharpness deterioration compared to their performance at f/45, so much that I can see it looking at the negatives on a light box without magnification. One, however, became only slightly less sharp -- the 300mm f/5.6 Nikkor W. With that lens, the difference was so small it can't be seen without magnification. While the loupe reveals minimal blurring, I wouldn't hesitate to say that a 2X optical enlargement might be indistinguishable (in terms of sharpness) from a contact print of the others at f/64.
What I take away from this, beyond the usual sample variation caveats, is that one ought not question another photographer's results without seeing them in person. The difference at f/64 between a vaunted ("clinically sharp") 300mm Fujinon A and Lenny's 300mm Nikkor W is astounding.
Peter De Smidt
5-Apr-2016, 10:25
Good stuff, Sal. Thanks for posting!
Drew Wiley
5-Apr-2016, 12:22
I miss Lenny. But I never did agree with his opinions about lens sharpness. For one thing, he scans; for another, tends to print small. Then third, his method of
evaluation is hardly scientific; and fourth, having owned, used, and done big critical enlargements from many of these lenses myself, I know the relevant variables, and can only continue to disagree with much of the above. There must be some inherent flaw in his technique that he has overlooked. Otherwise, diffraction gets pretty apparent with ANY 8x10 lens compared to f/64. Contact printers don't tend to notice this, nor do those whose main problem is an unflat film plane. But it is there. Those of us who routinely carry Fuji A and C lenses know what utterly superb performers they are, even in smaller 4x5 applications demanding still greater enlargement. But diffraction is the great equalizer.
Drew Wiley
5-Apr-2016, 12:25
... and yes, I did notice that this is a digital thread. So more layers of potential variables that have nothing to do with lens performance itself. The bottleneck is more likely in the workflow.
Sal Santamaura
5-Apr-2016, 13:14
I miss Lenny. But I never did agree with his opinions about lens sharpness. For one thing, he scans; for another, tends to print small. Then third, his method of evaluation is hardly scientific; and fourth, having owned, used, and done big critical enlargements from many of these lenses myself, I know the relevant variables, and can only continue to disagree with much of the above...Drew, did you actually read what I posted today? What might be "unscientific" about how I went about this comparison (Looking at the negatives on a light box, both with and without the aid of a loupe)? What variables might have inlfuenced the outcome? All my holders were purchased brand new after being selected from store stock by depth checking a much larger number than ultimately purchased; they're the pick of the litter. There were no substantive changes in temperature or humidity between when the film was loaded and exposures were made. The camera back was vertical -- no film sag.
...There must be some inherent flaw in his technique that he has overlooked. Otherwise, diffraction gets pretty apparent with ANY 8x10 lens compared to f/64...Forget Lenny's "technique." There's no flaw in how I went about this experiment. As stated, with seven of the eight lenses, sharpness degradation at f/64 WAS readily apparent (compared to f/45) looking at negatives on a light box with the unaided eye. For the 300mm f/5.6 Nikkor W, it was not; a loupe was necessary to see the surprisingly small effect of diffraction with that exceptional lens.
...Those of us who routinely carry Fuji A and C lenses know what utterly superb performers they are, even in smaller 4x5 applications demanding still greater enlargement. But diffraction is the great equalizer.I own EBC multicoated Fujinon A lenses in 180mm, 240mm, 300mm and 360mm focal lengths. In addition to the 8x10 test described in this thread, I also recently compared the 240mm A to a 240mm Germinar W, both at f/32 for 5x7 use. The Germinar was far, far sharper. At the same time, I compared the 300mm A to a 300mm f/9 Nikkor M, again at f/32. The Nikkor was far, far sharper. Again, all holders' depth confirmed as spot on, etc. Several months ago, I also compared the 360A on 4x5 to a Schneider 350mm f/11 Apo Tele Xenar Compact and 355mm Kern Dagor, all at f/22. In that case the Fujinon was sharpest, but I wonder whether it would have been had the competition included a 240mm Nikkor W. I don't own the latter lens, so can't say for sure. As for Fujinon C lenses, my post today indicates the 450mm version isn't bad, but doesn't match the sharpness of the other two 400mm+ optics I tested it against. I once had a 300C, but sold it, since it exhibited extremely low contrast. Finally, I have and use a 600C, but there's no modern optic to measure it against in that focal length.
Bottom line: diffraction is the great equalizer, except when it isn't. And one ought not question another photographer's results without seeing them in person.
What variables might have inlfuenced the outcome?
The most obvious variable is that the lenses are used and might be out of tolerance from factory specs, have cleaning marks, etc. And there is obviously some variation in lens performance even when purchased new. Shooting at f64 does tend to amplify surface defects on lenses, no? So the difference between the Fuji 300C and the Nikkor 300 might be attributable to cleaning marks on Fuji's somewhat soft older coatings.
Sal Santamaura
5-Apr-2016, 13:32
The most obvious variable is that the lenses are used and might be out of tolerance from factory specs, have cleaning marks, etc...All lenses I own were either purchased new or, if discontinued models, bought after extensive searches for pristine examples. There are no cleaning marks on any of them. I did end my first post in this thread today with the phrase "usual sample variation caveats."
...So the difference between the Fuji 300C and the Nikkor 300 might be attributable to cleaning marks on Fuji's somewhat soft older coatings.I mentioned having owned a 300mm f/8.5 Fujinon C and selling it due to low contrast, the only such experience I've ever had with a brand new lens. The recent comparison test between my pristine 300mm f/9 Fujinon A and my 300mm f/9 Nikkor M at f/32 could not have been influenced by cleaning marks on the Fujinon -- there are none, period.
Drew Wiley
5-Apr-2016, 13:39
Here is the kind of thing I have every reason to quibble with. Let's take that 450C for example. People stick that on a 4x5 with insufficient support, obviously a long
bellows extension, maybe a stupid ballhead, then lo and behold, get less than ideal results. Or they forget what a huge image circle of light it collects, so don't
shade it sufficiently. On the other hand, I wouldn't hesitate to use it even with a roll film back because it's so damn sharp. All these optics degrade a bit below
f/32, then dramatically more between f/45 and f/64. Just depends on your degree of enlargement whether this is a practical issue or not. Then, let's take my Fuji
360A. The Kern dagor might be a legendary cult lens, but is nowhere in the same league. Nor is any general purpose plastmat I've ever used. But again, it has a
big image circle and one has to be conscious of flare, though the multicoating does handle this a bit better than the equivalent G-Claron. I base this on big Cibachromes directly enlarged. Once somebody starts talking DPI the whole question is skewed by digital complications of distinctly lower expectations. Holder
depth means nothing if this pertinent variable isn't in relation to a vacuum system of perhaps adhesive holder. Anytime I enlarge bigger than 20x24 I use a precision back, otherwise nitpicking alleged lens variables is MEANINGLESS. Every single lens you've mentioned so far is capable of superb results. Very few
filmholders are adequate for the task. And don't forget the variable of shutter vibration, which of course its directly related to the mass, extension, and support of any given camera itself. For example, my Fuji 600C gives me quite sharp results with my 8x10 folder directly atop a Ries tripod (assuming no wind), but my
4x5 Norma has a problem with that big shutter; yet no problem at all with a 450C in no.1 shutter. So apples to apples, even very similar optical designs like
355 G Claron vs 360 Fuji A : the Fuji will give sharper results due to the lower vibration small shutter, yet impose a bit of mechanical vignetting due to that same
shutter in ULF situations (no problem at all with 8x10). All kinds of variables come into play. ... So now lets throw in the Nikkor M remark. It's a way smaller
image circle than a Fuji A; so yes, maybe center of image performance will differ; but the A is going to have distinctly better edge and closeup performance, esp
on 8x10 film. But I'd defy anyone to distinguish which of these two lenses made an immaculate 30x40 high gloss (polyester) print from 4x5 film itself. Even a low power loupe wouldn't do it, nose up to the print. At a certain point it's all overkill. If I'm on a long backpack trip, I'll pack the M for its light weight. If I'm
shooting closeups or 8x10, the Fuji A is the superior optic. I don't even use the Kern 14" much anymore. But then again, in most cases you probably couldn't even distinguish in print when I have. I just don't like that bigger shutter on 4x5 - want more mass behind it.
I am reading with interest because I am shopping for a new (to me) 300mm lens. I have a Fujinon-W inside lettering with some bad scratches that just isn't doing it; I have a couple of barrel lenses that are quite sharp, 2 fitted to Packards, but I would like a 'normal' 8x10 lens with good contrast and sharpness, in modern shutter. I was going to try another Fujinon (mostly for the price), but from your post I should be looking for a Nikkor. The extra $100 or whatever won't kill me, but I'm tired of buying bad lenses.
I have a couple of new Fujinons (to me) that I'm going to test first, a 75/5.6 for my 4x5 kit and a 250/6.7 for 8x10. If the latter is sharp, I may stop there.
Peter De Smidt
5-Apr-2016, 13:50
There is a fair amount of sample-to-sample variation, as others have pointed out. See Chris Perez and Kerry's lens tests, for instance. I would not conclude that a given 300 Nikkor will be better than a specific Fuji 300 on the basis of a test of one sample.
Sal Santamaura
5-Apr-2016, 13:51
I am reading with interest because I am shopping for a new (to me) 300mm lens...I would like a 'normal' 8x10 lens with good contrast and sharpness, in modern shutter...from your post I should be looking for a Nikkor...If you're going to use it on 8x10 at f/45 or (especially) f/64, you should absolutely be looking for a 300mm f/5.6 Nikkor W. Even sample variation couldn't significantly diminish the huge margin by which it beat the others.
...I have a couple of new Fujinons (to me) that I'm going to test first...a 250/6.7 for 8x10. If the latter is sharp, I may stop there.Depends on what apertures you shoot at. If at f/45 and (especially) at f/64, I think the 300mm f/5.6 Nikkor W would be much sharper, sample variation notwithstanding. Mine's not for sale, though. :)
Sal Santamaura
5-Apr-2016, 13:54
...I would not conclude that a given 300 Nikkor will be better than a specific Fuji 300 on the basis of a test of one sample.The margin of superiority in my results leads me to conclude it's a very good bet that the Nikkor W would be. I'd be more concerned about extrapolating from one focal length to another within a given manufacturer's lens line. Not all Nikkor W focal lengths are created equal, nor are all Apo Sironar S focal lengths, all Fujinon A focal lengths, etc.
Drew Wiley
5-Apr-2016, 13:57
Nonsense. If you're only talking 4x5 and need compact lenses (vs big studio clunkers in no.3 shutter), you can go Fuji 300C, 300A (rare), Nikkor 300M, Apo Ronar (Rodenstock), or just stick with that 250/6.7 you already have. You'd have to be one serious big printmaker to ever detect the difference in results. Believe whomever you wish. I don't care. We're all just splitting hairs here. There are all kinds of damn good relatively modern lenses out there to choose from. The
only reason I stopped using a 250/6.7 was that it was stolen. I replaced it with a 250 G-Claron which turned out to be even sharper, then added a 240 Fuji A, which is even better yet, and has just as big an image circle on 8x10. Gosh, yeah I have some seemingly redundant duplicate choices in my kit; but that's because their predecessors have seen a lot of hard outdoor usage and might not last the duration. Fuji A's and C's, G-Clarons, Nikkor M's - it's almost impossible to go wrong with any lens in these series. The 250/6.7 is an older lens, but a distinct keeper if you already have one.
Sal Santamaura
5-Apr-2016, 14:14
Here is the kind of thing I have every reason to quibble with. Let's take that 450C for example. People stick that on a 4x5 with insufficient support, obviously a long
bellows extension, maybe a stupid ballhead, then lo and behold, get less than ideal results. Or they forget what a huge image circle of light it collects, so don't
shade it sufficiently. On the other hand, I wouldn't hesitate to use it even with a roll film back because it's so damn sharp. All these optics degrade a bit below
f/32, then dramatically more between f/45 and f/64. Just depends on your degree of enlargement whether this is a practical issue or not. Then, let's take my Fuji
360A. The Kern dagor might be a legendary cult lens, but is nowhere in the same league. Nor is any general purpose plastmat I've ever used. But again, it has a
big image circle and one has to be conscious of flare, though the multicoating does handle this a bit better than the equivalent G-Claron. I base this on big Cibachromes directly enlarged. Once somebody starts talking DPI the whole question is skewed by digital complications of distinctly lower expectations. Holder
depth means nothing if this pertinent variable isn't in relation to a vacuum system of perhaps adhesive holder. Anytime I enlarge bigger than 20x24 I use a precision back, otherwise nitpicking alleged lens variables is MEANINGLESS. Every single lens you've mentioned so far is capable of superb results. Very few
filmholders are adequate for the task. And don't forget the variable of shutter vibration, which of course its directly related to the mass, extension, and support of any given camera itself. For example, my Fuji 600C gives me quite sharp results with my 8x10 folder directly atop a Ries tripod (assuming no wind), but my
4x5 Norma has a problem with that big shutter; yet no problem at all with a 450C in no.1 shutter. So apples to apples, even very similar optical designs like
355 G Claron vs 360 Fuji A : the Fuji will give sharper results due to the lower vibration small shutter, yet impose a bit of mechanical vignetting due to that same
shutter in ULF situations (no problem at all with 8x10). All kinds of variables come into play. ... So now lets throw in the Nikkor M remark. It's a way smaller
image circle than a Fuji A; so yes, maybe center of image performance will differ; but the A is going to have distinctly better edge and closeup performance, esp
on 8x10 film. But I'd defy anyone to distinguish which of these two lenses made an immaculate 30x40 high gloss (polyester) print from 4x5 film itself. Even a low power loupe wouldn't do it, nose up to the print. At a certain point it's all overkill. If I'm on a long backpack trip, I'll pack the M for its light weight. If I'm
shooting closeups or 8x10, the Fuji A is the superior optic. I don't even use the Kern 14" much anymore. But then again, in most cases you probably couldn't even distinguish in print when I have. I just don't like that bigger shutter on 4x5 - want more mass behind it.That's an awful lot of deflection / subject changing. My camera is an 8x10 Phillips Compact II, upon a sturdy support system in no-wind conditions, not a 4x5. The sharpest 300mm lens has exactly the same image circle as the least-sharp 300mm lens' image circle. The sharpest 300mm lens (the sharpest of all eight lenses) is in a Copal 3 shutter; the least sharp 300mm lens is in a Copal 1 shutter. None of the lenses I posted about in this comparison are 360mm. The degree of enlargement necessary to see (without magnification by a loupe, i.e. with the naked eye) that seven of the eight lenses degrade dramatically between f/45 and f/64, but the 300mm f/5.6 Nikkor W doesn't, is 1X. No enlargement. I mentioned the Nikkor M in response to another person's comment. It wasn't part of the eight lenses in this comparison. I don't use it on 8x10.
It might be a bitter pill to swallow, but one ought not conclusively discount another photographer's results without having seen them in person. Lenny was right. I've duplicated his results.
Sal Santamaura
5-Apr-2016, 14:26
If you're going to use it on 8x10 at f/45 or (especially) f/64, you should absolutely be looking for a 300mm f/5.6 Nikkor W. Even sample variation couldn't significantly diminish the huge margin by which it beat the others...
Nonsense. If you're only talking 4x5 and need compact lenses (vs big studio clunkers in no.3 shutter), you can go Fuji 300C, 300A (rare), Nikkor 300M, Apo Ronar (Rodenstock), or just stick with that 250/6.7 you already have....We're all just splitting hairs here...It's not nonsense. My response stated "If you're going to use it on 8x10 at f/45 or (especially) f/64..." Those are the conditions under which I tested and that's the format which requires substantial coverage. On 4x5, where one would be using larger apertures, and under conditions I neither tested nor reported on, the Fujinon 300mm f/9 A might be sharper than the 300mm f/5.6 Nikkor W, as might the 250mm f/6.7 Fujinon W. But that's not the format I read a question to be asking about.
...Fuji A's and C's, G-Clarons, Nikkor M's - it's almost impossible to go wrong with any lens in these series...This thread isn't about "going wrong with" those lenses or formats other than 8x10. It's about how Lenny tested his 300mm f/5.6 Nikkor W at f/64 and didn't find the resulting negative wanting for sharpness compared to f/45. I've duplicated that result. No amount of arm waving about irrelevancies will change the facts.
Peter De Smidt
5-Apr-2016, 14:31
The margin of superiority in my results leads me to conclude it's a very good bet that the Nikkor W would be. I'd be more concerned about extrapolating from one focal length to another within a given manufacturer's lens line. Not all Nikkor W focal lengths are created equal, nor are all Apo Sironar S focal lengths, all Fujinon A focal lengths, etc.
I don't own either. I have a Symmar-S and a Graphic-Kowa in that focal length. I don't have a dog in that fight. Your claim that Nikkor 300 Ws are likely superior across the board to Fujinon Ws, though, does not follow. You might've had an outstanding version of the Nikkor and a terrible version of the Fujinon. There's a reason that empirical scientific testing depends on large sample sizes and repeatability, including repeatability by other testers. Your test shows that for your system, and how you used the lens, that one lens was superior to the other. That's valuable to know, but basing a generalization about the likely performance of other lenses would be premature at best.
Sal Santamaura
5-Apr-2016, 14:44
...Your claim that Nikkor 300 Ws are likely superior across the board to Fujinon Ws, though, does not follow...I said that 300mm f/5.6 Nikkor Ws are likely superior to 300mm Fujinon Ws, not Fujinon Ws "across the board." My experience has been that, for a given lens line, there's usually a "sweet spot" focal length. Perhaps in the Nikkor W line 300mm was it.
...You might've had an outstanding version of the Nikkor and a terrible version of the Fujinon. There's a reason that empirical scientific testing depends on large sample sizes and repeatability...While there certainly is sample variation, something I always point out, the margin of superiority in this case, even if my 300mm f/5.6 Nikkor W is the best one ever assembled and my 300mm f/9 Fujinon A / 300mm f/5.6 Fujinon W are the worst ones ever to roll of Fuji's line, is so high that I'm unabashed in making the prediction.
...repeatability by other testers. Your test shows that for your system, and how you used the lens, that one lens was superior to the other. That's valuable to know, but basing a generalization about the likely performance of other lenses would be premature at best.Again, the margin is sufficiently large for me to generalize, but I encourage those who own other samples of these lenses to duplicate the comparison. I've spelled out all the conditions. Please have at it. :)
Drew Wiley
5-Apr-2016, 15:24
These simply aren't scientific results. You'd have to design an optical bench and have something truly flat as your target. Kodak once made TMX or microfilm glass
plates for such purposes, though with color film, only a precision vac filmholder would do. And as far as "batch variation" in fully modern manufacture is concerned, "the usual suspect", I doubt it unless your statistical sample base is significant (non single uses has that kind of quantity of anything), and unless you
first rules out the other suspects. But there are also special application issues. The reason I typically carry a Fuji 360A in that focal length is that I'm an opportunistic shooter. I frequently encounter subjects near macro, where this lens or a G-Claron is going to perform significantly better than a general purpose lens. Or I might have an architectual subject, or be in the redwoods, where I need dramatically more rise than something like a 300M. But at the same time,
I might carry an old 360 Zeiss process tessar as well, because I prefer its out of focus rendering where selective focus is the name of the game. But overall,
a more relevant test, and a necessary one to pin down this given subject fairly, would first be to evaluate what is happening in those filmholders. Film sags,
acetate typically more than estar, and 8x10 significantly more than 4x5. Your center to edge findings with an ordinary holder are automatically defeated by this
very fact. That isn't science; it's rolling the dice and then blaming something else.
Drew Wiley
5-Apr-2016, 15:32
Sorry for the typos... I have just spent a lot of money getting that tendonitis in my fingers partially fixed. But the same comment I made to Sal applies to those
allegedly definitive tests by Perez and KT. They aren't scientifically valid either. Do you REALLY think that kind of casual "batch" testing is more tightly controlled than how modern lens manufacturers with serious engineers and machining equipment define their own quality control ?????????????????? Nonsense.
Anecdotal evidence which points us to look in a certain direction is great and helpful. As they say... Who knew ?
That being said, I have to agree with the wisdom of testing multiple samples under controlled conditions. When we remove all the variables, what seems to us like unshakeable evidence may indeed shake out.
It may be true that certain lenses - or certain focal lengths in certain lenses - are reliably superior, but the only way to prove it is to actually prove it.
Drew Wiley
5-Apr-2016, 16:21
Yeah, and one has to look at what lens manufacture has been by the "big four" ever since the mid-60's. The quality controlled equipment by any one of them probably runs into many millions of dollars. Sure, some lens designs are inherently better than others for certain purposes, and each might have their forte.
For example, the Nikkor M has only six air/glass interfaces, plus multicoating - the ultimate evolution of the tessar design. So the contrast and hue differentiation are superb. But other kinds of lenses are superior at other things, like a big image circle, or macro to infinity versatility. Nobody has a perfect batting average. There were unanticipated cement issues with the 80 and 110 Apo Symmars for example. Back when the big camera stores still had pro staff and knowledgeable
salesmen, I once heard one of them remark that he had never seen a bad Fuji lens. I believe it.
Jac@stafford.net
5-Apr-2016, 17:06
These simply aren't scientific results. You'd have to design an optical bench and have something truly flat as your target.
We humans are not scientific targets. We do not expect our view to be flat. We interpolate. And we do not see everything in terms of resolution. If we view an image we like, we do not refer to lens designs to understand why.
.
Sal Santamaura
5-Apr-2016, 20:34
These simply aren't scientific results. You'd have to design an optical bench and have something truly flat as your target...They aren't and were never intended to be "scientific results." They're relevant results for those who shoot 8x10 landscapes at or near infinity. No, neither I nor anyone else interested in replicating the results has to design an optical bench or have something "truly flat" as a target. An Edmund chart, taped tightly to a fence, 50 feet from the camera, along with natural elements near it, is the perfect target for a real-world test.
...as far as "batch variation" in fully modern manufacture is concerned, "the usual suspect", I doubt it unless your statistical sample base is significant (non single uses has that kind of quantity of anything), and unless you first rules out the other suspects...For a significant period during my engineering career, I performed statistical quality control functions. I'm completely familiar with the concepts and practice. I always mention sample variation when discussing lens performance here. The 300mm f/5.6 Nikkor W's performance at f/45 and f/64 was so much better than the other tested lenses, I'm willing to wager (based on experience) that its 'winner' status cannot likely be attributable to sample variation.
...The reason I typically carry a Fuji 360A in that focal length is that I'm an opportunistic shooter. I frequently encounter subjects near macro, where this lens or a G-Claron is going to perform significantly better than a general purpose lens. Or I might have an architectual subject, or be in the redwoods, where I need dramatically more rise than something like a 300M. But at the same time, I might carry an old 360 Zeiss process tessar as well, because I prefer its out of focus rendering where selective focus is the name of the game...Neither a 300mm f/9 Nikkor M nor a 360mm lens of any type was part of my comparison. Scenes at macro range were not part of my test. Selective focus was not part of my test. My test was to evaluate sharpness of landscape subjects at near-infinity infinity distances when exposed at f/45 and f/64. That is all. And my results confirm what was stated in the OP.
...a more relevant test, and a necessary one to pin down this given subject fairly, would first be to evaluate what is happening in those filmholders. Film sags, acetate typically more than estar, and 8x10 significantly more than 4x5. Your center to edge findings with an ordinary holder are automatically defeated by this very fact...There's no further test necessary to "pin down this given subject fairly." To reiterate, my holders are all depth checked and hand-picked. There is no significant depth variation between their centers and edges. There is no film sag. The 8x10 Kodak polyester-based film I used is, in my experience, the most rigid available. I've previously depth-checked it after loading into these holders and, when held vertically, reflections in the emulsion from linear objects were straight. Everything had a long time to reach equilibrium with environmental conditions.
...That isn't science; it's rolling the dice and then blaming something else.You can wave your arms until they fall off, but it doesn't change the fact that my results confirm the OP. A 300mm f/5.6 Nikkor W at f/64 is vastly sharper than the other lenses I compared it to, and more than sufficiently sharp to make very crisp enlargements where the other lenses would suffer. Remember, I own all those other lenses, and use them in varying circumstances for different reasons. I've not until now made pictures with them at f/64 and don't plan to in the future. I've not packed the 300mm f/5.6 Nikkor W great distances and don't plan to in the future. But, if I want to make a photograph on 8x10 film of a subject at distance, need great depth of field and can do this close to my car, I wouldn't hesitate to use the 300mm f/5.6 Nikkor at f/64. It's the only lens among those I tested that I'm willing to say that about. And it confirms the OP's contention.
There's neither 'blaming something else' or 'rolling dice' involved. While my test conditions were not in accordance with your idea of 'science,' they were totally controlled for this practical, relevant comparison. Again, I encourage anyone who owns these lenses to conduct their own tests and post the results here. My money is on most, if not all, 300mm f/5.6 Nikkor Ws exhibiting far less diffraction blur at f/64 than people expect. I look forward to hearing from those who follow up, not just those who speculate and pontificate.
fishbulb
6-Apr-2016, 09:37
Those of us who routinely carry Fuji A and C lenses know what utterly superb performers they are, even in smaller 4x5 applications demanding still greater enlargement. But diffraction is the great equalizer.
It is sad that people still believe the "diffraction is the great equalizer" myth. It has been proven many times to be empirically false.
A lens that has fewer optical aberrations will appear sharper than another lens, even when stopped down. Likewise, a higher-resolution film/sensor will be sharper than a lower resolution film/sensor, even when stopped down.
Even under the severe diffraction at f/64, a sharper lens will outperform a less sharp lens. Just go and test a 1800's meniscus lens against a modern computer-designed lens, and see which is sharper at f/64...
For example, there are some good articles on the lens rentals blog (http://www.lensrentals.com/blog/2013/03/overcoming-my-fentekaphobia/) (this one too (https://www.lensrentals.com/blog/2016/01/what-actually-happens-when-you-stop-down-a-lens/)). Or for the impact of sensor resolution, see here (https://www.onlandscape.co.uk/2012/08/the-diffraction-limit-how-small-is-too-small/).
You can also see this in lens review online. Compare, for example, the old Sigma 50mm (http://www.photozone.de/nikon_ff/616-sigma5014ff?start=1) vs. the new Sigma 50mm art (http://www.photozone.de/nikon_ff/959-sigma5014dgfx?start=1). Same test camera, same conditions, same tester, same methods. Even stopped down to where diffraction is killing resolution, the better lens is still the better lens.
Drew Wiley
6-Apr-2016, 09:41
If this is your red line, Sal, then you're utterly wasting your time even nitpicking lenses. I've run 8x10 tests precision filmholder versus conventional where plane
variations in the latter (due to film bowing or sag in the vertical position, not a bad holder itself) was a far greater factor than anything related to one modern lens
versus another, or even minor diffraction issues. Unless someone here is an optical engineer, I'd suspect that optical manufacturers in the 1920's had better testing gear than any of us do. Having sold machinist equip at one time, and been on a first name basis with even NASA opticians, I'd suspect quality control today is pretty astounding when it comes to pro lenses. Yes, I do respect the cumulative know-how of the many users on forums like this, and the associated reputations or characteristics of certain lenses via lots of real world experience. But to go around saying you have no sag in your holders is utter nonsense. Hold up your holder and film in various positions with a strong linear light source (like bare fluorescent tube), with the darkslide removed. The light will be wavy or distorted. I personally check non only my holders, but the camera back itself with a bar of precision ground flat stock and a depth micrometer through it; in other words, tolerances within 1/1000 inch. That does zero to keep the film itself truly flat. When I contemplate big enlargements, or something critical like
an enlarged dupe in the lab, a precision vac holder makes all the difference in the world. In the field, I routinely use adhesive holders for 8x10 color work (I rarely print b&w larger than 20x24, which is a very modest enlargement for 8x10). Some sheet films are stiffer than others, and some camera angles (like
pointing downward) are more prone to sag than others; but it is always there to some extent. There is a reason that astronomers used glass plates rather than
sheet film in the old days. Otherwise, they'd be wasting their time. And yes, you are rolling the dice. You refuse to acknowledge the weakest link in this fashion
of testing. Might as well be throwing darts with fogged up glasses.
A lens that has fewer optical aberrations will appear sharper than another lens, even when stopped down.
Especially when stopped down. Look at a simple diagram of the light rays through a lens wide-open vs. at f64 to see why. Aberrations and surface defects are magnified the more you stop down.
Drew Wiley
6-Apr-2016, 10:22
Back to the "us versus them" opinion dept: How many of you saw in print when Sinar formally published that the weakest link in image sharpness was the flatness of film in the holder itself? Of course, people like Sinar-Bron knew absolutely nothing about quality control or precise machining, did they? Even Swiss watches are made with soggy cardboard and a bandsaw blade connected between a willow stick and a hound dog tail. But that's back when they tried to market an alternative platen-back 4x5 holder, which was so damn expensive it never caught on, along with the more practical adhesive system for 5x7 and 8x10 holders which people quickly learned to clone far more affordably, and had a distinct applications for. And people knew how to make even more precise vacuum holders for at least studio applications right along. There are a few minor tricks to it; but any thoughtful shop dude can do it. Yeah, unless I am after some special pictorial effect in a given lens, I buy the best I can afford. But I know that all this nitpicking is an utter waste of time unless the other variables like consistent
film plane flatness and good lens shading are likewise controlled.
Sal Santamaura
6-Apr-2016, 11:46
...I look forward to hearing from those who follow up, not just those who speculate and pontificate.Also not those who repeat irrelevant information without having read what I wrote that already addressed it.
Let those reading this thread judge for themselves. Some appear to be doing just that.
Drew Wiley
6-Apr-2016, 12:04
This is neither speculation nor pontification on my behalf, Sal. ULF shooters went crazy sticking little tabs of putty or ATG tape on holders to try and prevent sag. Serious concerns like Sinar tried to reinvent the filmholder. Until that problem is solved, how can anyone trust your casual method of testing, or that of anyone else who just wings it. And even your opinion about various lenses differs from that of many others who use these same lenses. It's a crap shoot unless you interject some controlled objective methodology to it. No, not all lenses are equal at f/64. And probably no lens at f/64 is going to be equal to the very same lens at f/45 unless depth of field is itself the priority. But by definition, this forum is concerned with the behavior of sheet film under such circumstances. Bringing 35mm lenses into the discussion doesn't do anything to solve that - and please, Fishbulb, don't tell me something I haven't already known for decades. I'm not about to test some stupid Sigma lens with respect to 8x10 shooting.
Sal Santamaura
7-Apr-2016, 08:03
...ULF shooters went crazy sticking little tabs of putty or ATG tape on holders to try and prevent sag...8x10 isn't ULF.
...Serious concerns like Sinar tried to reinvent the filmholder...Note that Sinar's literature for its film holders showed results at large apertures, not f/45 or f/64.
...how can anyone trust your casual method of testing, or that of anyone else who just wings it...Not casual or "winging it." Controlled and repeatable.
...even your opinion about various lenses differs from that of many others who use these same lenses...They're not "opinions." They are observations based on testing of my samples. Always accompanied by caveats about sample variation. Delivered along with an invitation for readers to test other samples of the same lens models and post whether they've duplicated or refuted my results.
...It's a crap shoot unless you interject some controlled objective methodology to it...One more time: my methodolgy is completely controlled.
...probably no lens at f/64 is going to be equal to the very same lens at f/45...Nor does anything I've posted claim that it is.
...unless depth of field is itself the priority...I'm completely unable to grasp how prioritizing depth of field could have any effect on an objective assessment of a given lens' sharpness, when evaluating said sharpness by photographing an Edmunds chart at 50 feet distance and then viewing the negative with a magnifier. More arm waving.
...But by definition, this forum is concerned with the behavior of sheet film under such circumstances...No, actually this forum is about photography using cameras using sensors nominally at least four by five inches. Those sensors don't need to be film. Another irrelevant comment.
This is neither speculation nor pontification on my behalf...Bottom line: it's nothing but speculation and pontification. If/when you've actually obtained a 300mm f/5.6 Nikkor W and tested it against your 300mm f/9 Fujinon A, and/or any of the other lenses I compared my sample to, under the conditions I described, then evaluated the results, please post about it here. Until then, I'll neither repeat the responses I've already posted to irrelevancies you bring up nor address any further arm waving you might engage in.
Drew Wiley
7-Apr-2016, 13:23
Sal, I'm not questioning your reason for disliking a Fuji 300W. I've never owned one of these, nor will I. I have no use for big clunky studio plasmats. Yet even
with this specific lens type there were many years of evolution, right up to the CMW line, which might or might not match your given stereotype. But there is nothing objective about you standard of evaluation. Optical benches exist for a reason. No lens designer tacks up a piece of paper on a fence post. Sure, I've stuck a postage stamp on a wall sixty feet away and then looked at the GG image with a 10X magnifier. It tells me something, but not how shutter vibration might interact, not about film plane issues, not about potential weaknesses in the tripod support, and maybe not a good enough view of the corners of the field to discuss things like pupilary distortion. I have set up elementary optical benches for such things. And even "sharpness" has different levels of interpretation. That's why so many of us have different lenses even of the same focal length that might all be quite sharp, but still render that sharpness with a somewhat different look, best suited to different applications. The biggest complaint I have in all these casual evaluations is the routine default of blaming lens to lens
batch inconsistency for what are far far more likely uncontrolled variables in the alleged testing method itself. Your consistent denial of film plane issues in ordinary 8x10 holders flies in the fact of what every serious camera maker and lens manufacturer has taken for granted for decades as an inherent limitations.
It is the very thing that makes one stop down to f/32 even when f/22 is optically sufficient with 4x5 format, for instance, and exactly why I routinely use full
adhesive holder with 8x10 film anytime I foresee the potential use of the shot for a print bigger than 20X24. It's not an accident why my big prints are sharp,
and the reason goes way beyond lens selection itself. Yes, you're welcome to ignore me. I'd post this anyway just because this kind of chronic misinformation
about testing seems so ubiquitous. Throw in visual web "proof" extracted from junk flatbed scanners and it get's REAL convoluted at times.
Peter De Smidt
7-Apr-2016, 13:27
Will more going back-and-forth change either of your opinions? Since the answer is clearly, "No." What's the point of continuing?
Kevin Crisp
7-Apr-2016, 14:30
Chronic misinformation...like the idea that you need adhesive to go over 20X24 from an 8X10 negative?
Sal Santamaura
7-Apr-2016, 15:23
Will more going back-and-forth change either of your opinions?...Drew's opinion never was, is not now nor will it ever be subject to change.
...What's the point of continuing?
...If/when you've actually obtained a 300mm f/5.6 Nikkor W and tested it against your 300mm f/9 Fujinon A, and/or any of the other lenses I compared my sample to, under the conditions I described, then evaluated the results, please post about it here. Until then, I'll neither repeat the responses I've already posted to irrelevancies you bring up nor address any further arm waving you might engage in.As quoted, I'll not continue responding to Drew in this thread. Unless he actually tests a 300mm f/5.6 Nikkor W as suggested and reports his results. :)
The point of every response I've posted to Drew's recent posts was never to change his "opinion." It was instead to make clear for other thread readers that a) Lenny's OP was a valid observation of a specific lens' behavior and b) Drew's arm waving / speculation / pontification must at all times be critically evaluated, challenged when appropriate and ignored when appropriate. I believe that's been accomplished. :D
"Since there is no one practical measure of the ability of a lens to produce a sharp image, the photographer can best evaluate a lens by comparing it with another lens." Saint Ansel
David
Drew Wiley
7-Apr-2016, 16:17
Kevin - what does adhesive "over" a 20X24 have to do with anything? Do you have even the slightest clue what I'm talking about? Get an old Sinar catalog.
Bingo. Pushback from somebody who apparently doesn't even understand the given discussion. And this is not "opinion"; Peter, it's recognized fact, unless you want to accuse people like Sinar Bron not having serious skin in the game. And have any of you seen any of St Ansel's 8x10's significantly enlarged? They're pretty damn mushy by modern standards or even commercial lab standards of his own era, no matter how tightly he pushed his bent nose up against the groundglass. Gosh.
Didn't realize I was up against Tennessippi moonshiners who still insist on leaded solder.
Kevin Crisp
7-Apr-2016, 16:49
I guess this is my last contribution to this thread as well. Yes, I knew exactly what you were talking about. By "go over" I meant "go bigger than," which I suspect is how most people would have read it. You took it, I guess, as a suggestion about somebody gluing something on top of something else. Maybe because you sell so much in the way of coatings and adhesives and such, per your earlier posts. Whether "push back" or not, I seriously still question the idea you'd need a special film holder to get a sharp modest enlargement from an 8X10 negative, especially in the aperture ranges under discussion in this thread. I think that is just plain misinformation, possibly discouraging to someone who doesn't know better.
I actually have seen Ansel's prints significantly enlarged and I did not find them "pretty darned mushy" by any means. There were lots of originals on display at the restaurant by Mono Lake, which may no longer be open. I believe the enterprise was one belonging to a grandchild. I've seen them elsewhere too in the flesh. I don't agree with your opinion (I know, your opinions are always "facts" to you...) that his prints were worse in their time than commerical lab product.
Not sure the descent to name calling serves any purpose. I've never had moonshine, or made it. I've been to Tenessee a couple times. I do use leaded solder for electrics repair, you "bingo-d" me there.
I believe that's been accomplished. :D
I believe we've moved on to necrohippoflagellation.
My mistake was assuming I logged into the Flat Film Society, when it really turned out to be the Flat Earth Society.
Think of it as a Black Swan event. An event very hard to predict that could not have been anticipated, so rare that we could not see it coming.
A lens is compared to other quality lenses of similar vintage and type, using sound methodology devoid of any possibility of flaw. And the results reveal that this lens is hugely superior in rendering an image at f/64 than any of the other lenses. This result could not be anticipated because it did not reveal itself, so far as we know, in any comparative testing provided by the manufacturer. Nor had the specific superiority been observed in empirical observations extending over more than two or three decades.
Sandy
B.S.Kumar
8-Apr-2016, 18:28
A lens is compared to other quality lenses of similar vintage and type, using sound methodology devoid of any possibility of flaw.
Sandy
While the Nikkor W 300mm is indeed a stellar performer, and Sal has performed the test as well as can be done outside a test lab, there are a couple of caveats:
The 420mm f/8 Fujinon L and the 300mm f/5.6 Fujinon W (single-coated version) are of much older vinatge than the Niikkor W 300mm. One also does not know if the 250mm f/6.7 Fujinon W used was the older version in the Seiko shutter, or the later Copal 1 version. I have one in a Copal 3 shutter that appears to have been factory modified or least professionally modified to accept this specific lens, which has the Seiko shutter threads. Perhaps the owner liked its performance so much that he went to the expense of getting a Copal 3 shutter modified. The 250mm f/6.7 lens was/is reputed to be great for portraits, where absolute sharpness is perhaps less important than a certain roundness and tonality. This lens was also superseded by the 6.3 NW version (marked W on the outside) and then the CM-W version.
Kumar
Sal Santamaura
8-Apr-2016, 20:39
...The 420mm f/8 Fujinon L and the 300mm f/5.6 Fujinon W (single-coated version) are of much older vinatge than the Niikkor W 300mm...And their performance at f/45 and f/64 was on par with the modern 450mm f/8 CM-W, not to mention in line with typical expectations for sharpness degradation at the smaller aperture. No differences that I can attribute to age of design or manufacture. And better than the 300mm f/9 A.
...One also does not know if the 250mm f/6.7 Fujinon W used was the older version in the Seiko shutter, or the later Copal 1 version...It's a very late sample in Copal shutter. There's no evidence it had been tampered with or re-shuttered before I bought it.
Drew Wiley
11-Apr-2016, 09:00
I do covet a Fuji 420L, even though its a bit of a beast, or even a 300L. I want this for its distinct Tessar "look" in older multi-bladed Copal 3s shutter. But there is absolutely no way on earth, except in the estimation of one individual, that this lens will have the resolution or coverage, RELATIVE TO focal length, equal to an A series lens. People do use strong tilt and rise at times, even at f/64, or perhaps especially at f/64, since it's those strong movements which often demand a small aperture to avoid mechanical vignetting. There's a reason that, unless you a very lucky, any 300 or 360 A typically sells for triple the cost of a 300 or 420 L in equal condition. Even a 240A is sharper and more apo-corrected than the 250/6.7, and even has virtually an equal usable image circle. And the 250/6.7 is one damn fine lens! Sal likes fine lenses just like I do, and I hope he enjoys them to the fullest. But hundreds of big prints have given me a somewhat different take on the specifics.
StoneNYC
11-Apr-2016, 11:38
Aside the normal bickering, a few thoughts.
Sal it's great you followed up and did your own tests.
Drew, to truly have a scientific analysis of lenses, you need to have digital technology to analyze it, one persons view through the loupe or a print done by a particular printer introduces new variables.
To both, this is a great amateur test.
To be more scientific you would need ...
30 or more lenses of each type tested for a legitimate sample size before introducing a confidence interval which from a sample size of 1 which would be a very poor confidence.
Tests performed in a lab on a solid stand with a vibration monitoring device to ensure lack of camera shake as a variable for each exposure's sharpness characteristic.
A batch developing system that is completely machine automated to reduce the variable of batch to back processing differences.
digital aperture measurements of all f/stop measurements for all lenses before and after each image was taken.
Consistent lighting to avoid and account for contrast changes and potential flare variables.
1:1 digitalized scan sections for examples of each sample
Center as well as edge to edge images, in other words, using just rise and fall to get to the edge doesn't account for center sharpness or falloff of each lens as you get farther out.
Comparable digital back scans of the same images for comparisons to notate differences between angles of light hitting pixels vs silver grains.
A true scientific test would be extensive and not something we could do at home.
I say this simply because the question was asked "what could be done to make this more scientific?" So those are some thoughts on why this isn't a scientific test.
Side note, my 300 C is very contrasty.
Anyway still an interesting set of comparisons. Thanks Sal for actually doing tests, but as I often have told Drew, showing your examples for us to view (like I believe Ken Lee did? Or someone else who was an early forum member) would greatly help us to see what you see. Yes this is a lot of work, but it would help your case. As they say, a picture is worth 1,000 words.
Thanks for taking the time to read.
Drew Wiley
11-Apr-2016, 13:49
Not only how X versus Y versus V pixels compare, versus again X versus Y versus Z specific films, but about how the different kinds of aperture blades interact
at small f-stops to create artifacts which might look different under a loupe than in an actual print. But like I already said, if the film plane isn't totally flat in the
first place, all bets are off. And what some of you perceive as contention or opinion is just the tip of the iceberg in terms of what many practitioners already know and rely on to get predictable results. Not all the chatter on this given subject is on this venue, not by a long shot. And it still absolutely astounds me that everything is fair game for discussion except the elephant in the room. But I don't care. Sal does post at lot of things I genuinely appreciate. I'll continue to do what is necessary for my own needs or those seeking analogous solutions.
Maris Rusis
11-Apr-2016, 16:35
I do lens comparison tests at various apertures which I reckon will unambiguously find which lens is better or worse or the same. The key is to look at the aerial image. I set up a couple of large format cameras side by side that have their backs replaced by telescope style focussing drawtubes. Telescope eyepieces, usually Plossls of various focal lengths, deliver selectable magnifications to highlight aberration and diffraction effects. A favourite infinity subject is the top of a power pole well above ground shimmer that has fine wires against the sky, insulators with specular highlights, and wood textures. By looking back and forth between eyepieces it's easy to pick lens quality differences. And it's downright gratifying to know which lens is best.
BUT:
The test shows only central image quality, not the edges of the image circle.
Actual image quality on film will be worse because of film sag, film resolution limits, halation, flare, etc...
Camera vibration, shutter vibration, wind vibration, tripod wiggle, etc will confound results.
The net outcome is that I know the best lens but what I end up with in the final photograph is an accumulation of errors (they never cancel?) from every step in the production process.
Drew Wiley
12-Apr-2016, 08:21
The protocol for people using film for scientific purposes, or anything analogous requiring image optimization inherently demands certain variables get ironed out
one at a time. True film plane is one of these. That is why Kodak continued making high-resolution glass plates for many decades after the invention of more practical but less precise film. In aesthetic photography, we can bend the rules any way we wish, and select lenses for net visual effect rather than precision if we
prefer. I do both, depending on my specific project, degree of intended enlargement etc. But since this thread is about hypothetical lens performance and not image "look", I was merely pointing out one of the the most frequent major obstacles to objectivity which generally gets overlooked. I find the aerial image technique, which Maris just pointed out, to be most effective when using film somewhat undersized in relation to the image circle, where really only the center
of the field generally comes into play. For example, roll film exposures using 4x5 gear and the same lenses I carry for full 4x5 film itself. This means greater
enlargements, yet potentially photographed at slightly wider apertures. Quality of film tightness, whether or not the roll film back tugs the rear standard out
of assumed position due to extra weight or bulk, etc - here again, true film plane becomes a misunderstood issue, where any given lens might get graded wrong
due to a different problem completely.
...The net outcome is that I know the best lens but what I end up with in the final photograph is an accumulation of errors (they never cancel?) from every step in the production process.
Photographing El Capitan from the meadow with the 11x14. Two exposures, same lens, nothing else moved. One dang negative is sharper than the other. Something must have happened to the lens! You turn your back on an Artar and they'll change on you! It's a Red Dot - must be a commie. It can't be the fault of the operator and his use of the lens-cap-as-shutter! :cool:
Drew Wiley
12-Apr-2016, 11:38
The solution was simple, Vaughn. If El Capitan was out of focus, just move the monolith either forward or backwards a bit.
Ken Lee
12-Apr-2016, 12:18
It can't be the fault of the operator and his use of the lens-cap-as-shutter! :cool:
Definitely not your fault, but to be truly scientific, you need to test several El Capitans.
StoneNYC
12-Apr-2016, 12:20
Photographing El Capitan from the meadow with the 11x14. Two exposures, same lens, nothing else moved. One dang negative is sharper than the other. Something must have happened to the lens! You turn your back on an Artar and they'll change on you! It's a Red Dot - must be a commie. It can't be the fault of the operator and his use of the lens-cap-as-shutter! :cool:
Haha!
Vaughn, it wasn't the lens, it was when you turned your back on the mountain, the mountain moved mid-shot!
:)
Definitely not your fault, but to be truly scientific, you need to test several El Capitans.
Sign me up. I'll start a Kickstarter immediately.
Drew Wiley
12-Apr-2016, 13:03
Or due to failure to use a tad of front tilt. Most of the cliff is not truly vertical. A couple of cliff-jumper chutists have proven that!
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