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moto-uno
19-Dec-2009, 19:49
Hello
I am wondering why my cityscape shots with Velvia 100F are noticeably sharper than with the Ilford Delta 100?Signs under an 8x loupe are easily read in the Velvia shots,not so with the Ilford.These are all 4x5.
Same lens,settings and bracketing etc.Should add that the Ilford were on contact prints.
I want to have a big enlargement and don't care if it's b&w or colour,but I just can't see the Ilford enlarging as sharply.Hope you can shed some light on this subject.
Peter

Gem Singer
19-Dec-2009, 20:31
Are you comparing apples to oranges?

As you know, Velvia is a color transparency film, and Ilford Delta is a B&W negative film.

However, you are comparing a positive B&W contact print (on print paper) to an original positive image on transparency film.

If you would compare the sharpness of the B&W negative to the sharpness of the color tranny. My guess is that they would be equally sharp.

BetterSense
20-Dec-2009, 01:50
But a contact print should be nearly as sharp as the negative, shouldn't it?

Armin Seeholzer
20-Dec-2009, 02:50
But a contact print should be nearly as sharp as the negative, shouldn't it?

No the paper has a much lesser resolution then a neg or pos!

Cheers Armin

Bruce Watson
20-Dec-2009, 07:16
But a contact print should be nearly as sharp as the negative, shouldn't it?

Nope. Especially not under a loupe.

Compare the two films side-by-side on the light table with a 10x (more or less) loupe. If you make both a color and a B&W exposure of the same scene without changing any of the camera settings, the B&W should be a tad sharper.

Note that part of what you are seeing as increased sharpness in the color tranny is just increased contrast information for your visual system -- contrasting colors can look sharper without actually resolving more. Perceived sharpness is often more about contrasts than it is about actual resolution.

SamReeves
20-Dec-2009, 10:01
I'm surprised we're looking at the grains of 4x5 film! ;)

Bjorn Nilsson
20-Dec-2009, 10:13
Good glossy b/w paper resolves maybe 10 linepairs per millimeter, while the Delta 100 should easily resolve more than 100 (maybe up to about 130).
While the 130 is indeed high resolution you will not get that with any LF lens, in fact you don't even get close to that number. You'd rather get 40 lp/mm (line pairs/millimeter) on a very good day using the best lenses available (like a Fuji A lens).
Also, take into consideration that any chrome film is made up from some 6-8 layers, while the b/w film has one. In fact Delta 400 or TMax 400 will be just about as sharp as the Velvia, but the Velvia will look much sharper on a light table before you start to look at resolution power.
Given that, what Bruce says makes very much sense. (He is a professional in this field.)

//Björn

Drew Wiley
20-Dec-2009, 10:26
Although Delta 100 can hold a lot of detail, it has relatively poor edge effect, so the
apparent sharpness might suffer with conventional developers.

Lenny Eiger
20-Dec-2009, 11:33
In our tests with Delta and TMax, in Xtol 1:1 with a Jobo, Delta won in the sharpness category.

However, that said, I tire of this conversation about resolution. Everyone is constantly quoting lens capabilities as if it were the last word. Perhaps if sharpness were the only thing important in an image, it is.

What about tonality? What about reproducing the scene in its original feel? Film size trumps resolution every time.

Lenny

Ed Richards
20-Dec-2009, 13:44
> Film size trumps resolution every time.

To expand on Lenny's point: Vision trumps film size - I am sure we have all seen amazing sharp and beautifully toned ULF contact prints that were really really boring, and 35mm shots we wished we had made.:-)

sanking
20-Dec-2009, 14:00
In our tests with Delta and TMax, in Xtol 1:1 with a Jobo, Delta won in the sharpness category.

However, that said, I tire of this conversation about resolution. Everyone is constantly quoting lens capabilities as if it were the last word. Perhaps if sharpness were the only thing important in an image, it is.

What about tonality? What about reproducing the scene in its original feel? Film size trumps resolution every time.

Lenny

And I tire of folks who confuse resolution with sharpness. They are not the same and someone with Lenny's knowledge and experience should know better.

And no, I don't agree that film size trumps resolution every time. It usually does, but there are many exceptions depending on the films being compared and the format sizes being compared, and print size. Bigger is usually better but don't bet your life on it always being so.

Sandy King

Ari
21-Dec-2009, 10:27
> Film size trumps resolution every time.

To expand on Lenny's point: Vision trumps film size - I am sure we have all seen amazing sharp and beautifully toned ULF contact prints that were really really boring, and 35mm shots we wished we had made.:-)

Amen to that.

Lenny Eiger
21-Dec-2009, 11:40
And I tire of folks who confuse resolution with sharpness. They are not the same and someone with Lenny's knowledge and experience should know better.


Of course I know the difference, I was just rattling off a quick one and wasn't perfectly accurate. As a result the I feel the point was missed.

The issue for me is what the print looks like. Our tools have a critical sharpness limit. The difference between smaller fstops and wider ones is almost imperceptible in a hybrid workflow. I appreciate depth of field more than having one area be insignificantly sharper (my bias).

That said, what is important to me is the tonality, the smoothness of the print, the ability of the print to reproduce a larger number of tones, and thereby bring the viewer closer to the experience of "being there" - or the feeling of what it is like to be there.

That is best done with a larger piece of film. Exceptions notwithstanding.

Lenny

Lachlan 717
21-Dec-2009, 14:16
Hello
I am wondering why my cityscape shots with Velvia 100F are noticeably sharper than with the Ilford Delta 100?

Peter,

If one is "noticeably sharper" than the other, the implication is that both are sharp to begin with (just one has greater sharpness).

Also, was the wind blowing at the time? Was your camera fully locked down? Were the shots taken near the San Andreas Fault? Without the sterile setting of a studio (not located on the San Andreas Fault!!), you have not introduced any controls into your testing. Thus, you are relying on erroneous data.

With these points in mind, forget about it and go shoot!!

moto-uno
21-Dec-2009, 17:25
Hi Everyone
I'm really pleased with all the responses.Now to clarify a few points.Conditions were quite controlled as my intent in this exercise was to compare the sharpness of these films.What was noticeable under the 8x loupe was that signs(both in black and white and colour) were not legible in the contact prints.And I do feel comfortable in comparing apples to oranges,because the analogy is, which delivers the most vitamin c(sharpness) per pound?My thanks go out to the fellow that suggested comparing the transparencies to the negatives instead of the contact prints.Now the differences are barely perceivable.I must admit I'm new to this large format stuff and thought the contact prints would be as good as it gets.This now begs the question,with just the sharpness in mind,do either of these film types transfer to enlargements better?Sure glad I joined this forum!! Regards,Peter

rdenney
21-Dec-2009, 17:49
This now begs the question,with just the sharpness in mind,do either of these film types transfer to enlargements better?Sure glad I joined this forum!! Regards,Peter

Contact prints are still as good as it gets in terms of tonality. Remember that paper is the same no matter how much (or little) the image is enlarged before printing on it. A large print might allow one to read those signs compared to a contact print, even if the contact print still appears crisper because the tonalities are less spread out.

Also remember that the best viewers can only resolve perhaps 8 line pairs/mm in a print without a loupe, and any smooth, glossy paper has more than enough resolution to exceed that threshold. Unless you plan to display contact prints and then provide loupes to your viewers, then don't worry about it.

There is no way that I can compare color transparencies to black-and-white film when printed. Both resolve well enough to show impressive amounts of detail in a reasonable enlargement. But the differences between them are so much bigger an issue than resolution (or sharpness) that resolution should really have little role in the decision of which to use, unless you intend to make black-and-white prints from color transparencies. Even then, you'll be constrained by the narrow range of transparency film long before notice any trivial difference in resolution.

Make big enlargements and look at the differences in those signs when they are big enough to see with the naked eye. You might be surprised.

Rick "suspecting the color transparency film appears sharper but resolves less" Denney

Oren Grad
21-Dec-2009, 18:11
What was noticeable under the 8x loupe was that signs(both in black and white and colour) were not legible in the contact prints.

Then the printing technique was faulty. B&W paper has way more than enough resolution to record an image with what will be perceived as perfect fidelity by the naked eye at any viewing distance. Nor should it be radically different in perceptible detail even under an 8x loupe.

paulr
21-Dec-2009, 19:53
Part of what your seeing is loss of sharpness from the contact printing process (small but visible). And part is that Velvia has just about the most pronounced edge contrast at medium resolutions of any film. If you look at Velvia's MTF curve, it's actually significantly above 100% at the resolutions that will make the most visible difference when -- you guessed it -- you're looking at it with loupe on a light box.

sanking
22-Dec-2009, 09:23
Of course I know the difference, I was just rattling off a quick one and wasn't perfectly accurate. As a result the I feel the point was missed.

The issue for me is what the print looks like. Our tools have a critical sharpness limit. The difference between smaller fstops and wider ones is almost imperceptible in a hybrid workflow. I appreciate depth of field more than having one area be insignificantly sharper (my bias).

Lenny

Sorry, but many people confuse resolution with sharpness and it is one of my pet peeves. I am sure you know the difference, but since many do not it is best to be as accurate as possible in our discussions.

Bruce has already nailed this pretty well anyway so no need to add much more.

The issue is indeed what the print looks like. However, ultimately that determination is highly subjective and depends on how each of us weigh the individual component of image quality. I personally find it impossible to single out, as a general rule, any one component of image quality as more important than any of the others because ultimately the major consideration is the intent of the artist.

Sandy

Greg Blank
22-Dec-2009, 22:45
I am going to second all the opinions saying that you really have to look at originals versus originals. That means film versus film. A print judged against a film original transparency is one step down.



Hello
I am wondering why my cityscape shots with Velvia 100F are noticeably sharper than with the Ilford Delta 100?Signs under an 8x loupe are easily read in the Velvia shots,not so with the Ilford.These are all 4x5.
Same lens,settings and bracketing etc.Should add that the Ilford were on contact prints.
I want to have a big enlargement and don't care if it's b&w or colour,but I just can't see the Ilford enlarging as sharply.Hope you can shed some light on this subject.
Peter

BetterSense
23-Dec-2009, 09:37
So what? Do you ever view a negative as a final work? It seems to me that one should view final output vs. final output, of whatever processes you are comparing.

mcfactor
24-Dec-2009, 08:22
I bet if you were to enlarge the negative about 4x it would look sharper or as sharp as the tranny. Contact prints look softer (but better toned) than enlargements (Adams notes this in "the print").

moto-uno
28-Jan-2010, 22:26
Hello Again
Well I put my money down and ordered 2 24"x30" enlargements,one of the Ilford and one of the Fuji.At these sizes the detail is astounding.No one passes by them without remarking.I then put my 8x loupe to each and was finally able to see hints of grain in them.Concerning myself with sharpness in this format was a display of naivete.Thanks again to all that responded to my inquiry.Now to try out 400 b&w.By and large most observers preferred the Ilford b&w.

Armin Seeholzer
29-Jan-2010, 08:59
So what? Do you ever view a negative as a final work? It seems to me that one should view final output vs. final output, of whatever processes you are comparing.

Not if I like to know wich film has higher resolution!

Cheers Armin

Drew Wiley
29-Jan-2010, 11:13
I find this thread about as relevant as asking what likes water better, ducks or geese?
When it comes to large format, how you go about printing something is going to have a much greater effect on apparent sharpness and than whether you chose a color neg or chrome film.

neil poulsen
31-Jan-2010, 06:16
After speaking to a well-informed Schneider Tech on a different matter, I may have just found the answer to this question. (Maybe.)

A lot of us know that lens designers optimize a lens by working with three different wavelengths. I was told that Schneider optimizes lenses by focusing these three separate wavelengths on different layers of color film. Alternatively, black and white film is flat. So, I would suggest that a developed sheet of color film whose layers align well with a given lens optimization will appear sharper than using the same lens on black and white film that does not have the different layers.

In particular, I was told that this is the difference between typical LF lenses and the newer Digitar lenses. Digital sensors are flat, so the Digitar lenses are optimized for flat surfaces. That is, the Digitar lenses are optimized by focusing the three wavelengths on the same plane and not on different layers. The gentleman said that Digitar lenses give very sharp results on black and white film, which is not layered and flat. (He said, Digitar lenses are sharper on b&w negatives than traditional LF lenses.)

So, I'm curious. What lens were you using? I ask, because it's my understanding that so called "Apo" lenses are optimized to focus three wavelengths sharply, whereas older lenses like Symmar-S lenses were optimized to focus only two of the three wavelengths.

Please bear in mind, I know very little about lens optimization. I'm merely repeating what I was told.

Nathan Potter
31-Jan-2010, 10:18
Neil, that's an interesting thought. I think however that there is not consistency in the thickness of the three emulsions between manufacturers so this tailoring of focal point in color films would be only partially effective. Also Depth Of Focus considerations in LF lenses would wash out the advantage pretty quickly. Of course with a completely planar sensor there could be considerable advantage in correcting for three colors at a single plane, Foveon sensors excepted.

Nate Potter, Austin TX.

Drew Wiley
31-Jan-2010, 10:31
Neil - that just doesn't make sense. Not all color films are layered the same, or are
even necessarily the same thickness. But the layers are very, very thin. How can
one even focus that accurately, especially since film isn't held perfectly flat except
in a machined vacuum holder?

paulr
31-Jan-2010, 10:52
The answer is very simple. It's all about Velvia's exagerated MTF at low resolutions. That and its high overall contrast and saturation, which increase our impression of sharpness. In terms of overall performance, including sharpness at higher resolutions and ability to capture very fine details, and information recoverable and sharpenable in a scan, films like TMX and delta outperform velvia by a huge margin.

Drew Wiley
31-Jan-2010, 14:27
Paul - once again, I refer back to how something gets printed. Tmax 100 and Delta
100 can hold a lot of detail, but the acutance of both is quite poor due to marginal
edge effect. In other words, conventionally printed, they don't look especially sharp.
With PS you can add a sharpening layer, or do so similarly by unsharp film masking
in analog to improve edge effect. But with a direct black and white print or looking through a loupe, they disappoint. Grainier film often print looking sharper because there is more "tooth" to the detail, even if there's less micro-detail initially.

sanking
31-Jan-2010, 15:26
Paul - once again, I refer back to how something gets printed. Tmax 100 and Delta
100 can hold a lot of detail, but the acutance of both is quite poor due to marginal
edge effect. In other words, conventionally printed, they don't look especially sharp.
With PS you can add a sharpening layer, or do so similarly by unsharp film masking
in analog to improve edge effect. But with a direct black and white print or looking through a loupe, they disappoint. Grainier film often print looking sharper because there is more "tooth" to the detail, even if there's less micro-detail initially.

Acutance with most films is determined both by film and by type of development. Films like Fuji Acro, Tmax-100 and Delta 100 may show normal or low acutance with normal processing, but both develop enhanced acutance from micro-contrast caused by enhanced adjacency effects with minimal type agitation routines using suitable developes and with some two-bath developers. The type of acutance that can be achieved with thesw types of development can be as effective as adding a sharpening layer in PS.

Sandy King

Drew Wiley
1-Feb-2010, 10:15
Thanks, Sandy. But when things get so complicated that I need to resort to stand
development, I just switch to another film. Don't have the patience for it. Among the
newer super-fine-grained films, I find Acros to have distinctly better edge effect than
TM100 or Delta 100, at least for my standard pyro routine. All depends on how big one
needs to enlarge too. If I was doing mural-size black-and-white, the requirements
would obviously be different from doing 16x20's or 20x24's from LF negs. With MF I
find myself using exclusively Efke R25, which has both exceptionally fine grain and
high acutance (but unfortunately, needs a fair amount of spotting).

sanking
1-Feb-2010, 10:30
Thanks, Sandy. But when things get so complicated that I need to resort to stand
development, I just switch to another film. Don't have the patience for it.

Drew, I said minimal agitation procedures, not stand or semi-stanfd development. Minimal agitation normally refers to four or five agitation cycles during development, with the film resting the remainder of the time. It is a pretty main line type of development, and was recommended by Ansel Adams himself. Most people find the procedures no more complicated than normal processing.

But minimal agitation will likely cause uneven staining with some Pyro developers, including PMK and WD2D, and I believe you use PMK? It does work fine with a number of other Pyro developers, including Pyrocat-HD and -MC and Rollo Pyro.

Sandy King

rguinter
1-Feb-2010, 10:42
... you have not introduced any controls into your testing. Thus, you are relying on erroneous data...

I wouldn't necessarily call it erroneous data... a better scientific term might be "confounding variables." Bob G.

Drew Wiley
1-Feb-2010, 13:13
Yes Sandy, I primarily use PMK in trays as my standard developer, although I often have other pyro tweaks on hand for special problems, including pyrocat. With HP5 I can dilute the PMK to get excellent printing characteristics just off the stain, but haven't gotten this to work with any other film. I bounce back and forth between a lot
of different LF films, partly for fun, partly to use up old inventory, sometimes for the
special characteristics of each - but development is almost never an issue - all these
negs seem to print dead on. I'm very comfortable with a lot of different film and
developer combinations. But reducing the agitation cycle of PMK isn't advisable, as you've already noted. There was a time when I did two-bath development, and somewhere back in my memory, water-bath, probably when Super-xx was still around.
Seems so much easier now, probably due to the progressive learning curve.

paulr
1-Feb-2010, 14:38
Paul - once again, I refer back to how something gets printed. Tmax 100 and Delta
100 can hold a lot of detail, but the acutance of both is quite poor due to marginal
edge effect.

Their acutance isn't poor at all, it's actually excellent. You're right that neither film produces edge effects under normal development. This will cause them to look less sharp than some other films, at certain magnifications. The trouble with edge effects is that they behave just like a sharpening filter, only without any user controls. The width of the mackie lines, and the spacial frequencies that they effect, are fixed. The effect will benefit prints at a particular range of magnifications / viewing distances.

Velvia looks brilliant on a light table through a 4X loupe. But there are other magnifications at which the sharpening effect will be too subdued or too coarse.

Drew Wiley
1-Feb-2010, 16:36
Paul, the difference is, that a Mackie line is generally very subtle, whereas PS often gets overdone. All related to the degree of magnification, of course, as well as the
specific film. But as a rough rule of thumb, thin emulsion films conventionally developed tend to have less edge effect. Strategically, the difference often defines
large format versus small format choice for me personally, along with speed and
linearity. Velvia is a completely different question. The graininess is most in the deep
blue-blacks which won't show even with a high degree of enlargement. I've heard
there's some scanning issues, however; but I print directly. I've got distinctly contrasty 30X40 Ciba prints made from even the old-style 4x5 Ektachrome 64 (a lot grainer under a loupe than the present stuff) which barely hint at any grain visually.

Drew Wiley
1-Feb-2010, 16:45
Related to above - LF prints I've made from even the old-style TM400 look sharper
than those made from TM100. But it would look just the opposite under a loupe or
through a grain magnifier on the easel. Of course, a big open sky might show some
peppering with the old stuff. Yet I don't know how one can compare apples with oranges when you've got factors like pyro stain versus grain quality versus dye clouds
versus orange masking in color negs versus diffusion light sources, etc.

rdenney
2-Feb-2010, 08:41
Velvia is a completely different question. The graininess is most in the deep blue-blacks which won't show even with a high degree of enlargement. I've heard there's some scanning issues, however; but I print directly. I've got distinctly contrasty 30X40 Ciba prints made from even the old-style 4x5 Ektachrome 64 (a lot grainer under a loupe than the present stuff) which barely hint at any grain visually

I've made prints from Velvia 6x7 transparencies at 16x20, which is about the same magnification as your 30x40 prints from 4x5. I scanned the transparency in a Nikon scanner at 4000 spi. At 100% on the monitor, and with a loupe on the print, that deep blue sky is the only place I can see any hint of grain, but I can't see it at all with the unaided eye. And the acutance is crisp, to say the least. When I attempted a black-and-white conversion, the grain was a bit more apparent, though probably because of the way I tried to "filter" the image to get the tones I wanted (I went extremely deep on red filtration to darken the sky dramatically down to about Zone III and render some sunlit stones at about Zone VIII), which required some fairly extreme moves in the curves tool. That would accentuate the grain, to be sure. A deep red filter on black and white film would have covered most of that distance at the outset.

I've had similar problems with graininess in sky areas when scanning from color negatives, but I suspect these have been related to running out of the scanner's ability to see through the densest part of the negative. I have not had the problem with film scanners--only with earlier and cheaper flatbeds. The Nikon scanner can handle the range of transparencies, so that's what I've been using for the most part since I've owned it. But I am going to be experimenting with negative materials again now that I'm planning to scan 4x5 in an Epson flatbed.

Paul's description delves into issues I've barely ever considered, but I see the sense in it--at some level. For practical print-making, however, I'm not sure the relationship between magnification and apparent acutance has been obvious to me. Maybe I just don't make big enough prints to have noticed it. I'll have to keep my eyes open in the future, now that I'm aware of it.

Rick "for whom grain in black-and-white renderings from color sources was more related to big tonal moves than anything" Denney

sanking
2-Feb-2010, 09:07
If you are scanning color negatives with a dedicated film scanner I would recommend that you try fluid mounting. I get much finer grain and more micro-contrast with fluid mounting than with dry mounting when scanning color negatives with a film scanner, though your results may vary.

The width of adjacency effect lines definitely varies a lot with film, developer and type of agitation and must be taken into account when considering the magnification ratio. If they are very wide to begin with, and the film is magnified many times, the look can be quite unattractive. You see this often with folks who work with high resolution 35mm cameras and high acutance developers.

High acutance developers have a lot of potential with LF film that will be contact printed as it is virtually impossible to over-do the lines for contact printing, and they can add a real bite to the sharpness.

Sandy King

moto-uno
13-Feb-2010, 16:01
Hello
In reference to Neil's question I was using Kodak 203 mm lens that the lens serial number tells me was made in 1941!It also so has the "L" in the circle.I still have requests to bring the prints back to the shop.In response to Drew's remark,now I'm really interested in trying some of Ilfords 400 b&w film,because as I mentioned earlier these two enlargements seemed impressively sharp.Thanks again for following up.