Format for 60x75 inch Gallery Prints - 4x5 or 8x10?

[e2aa]

This might seem like a dumb question, but please bear with me.

I use MF digital usually, but want to get into LF for my fine art work as I am tired of stitching.

Next week, I plan to buy a 4x5 or 8x10 Arca Swiss F-Metric Compact (or similar).

I shoot primarily 5-second (plus) exposures of landscapes and interiors (devoid of people) in color. My prints need to be ~60x75 inches (strict requirement). In terms of workflow, I drum scan, modify in PS and print digitally.

My questions:
1) What is the absolute best ~150mm (or comparative 8x10 normal lens) lens I can buy for each camera?
2) If I use a top Rodenstock or Scheider normal lens, will I be able to achieve a high quality 60x75 inch print, with solid tonality and detail, from the 4x5 (which I am leaning towards this due to size considerations)?
3) Assuming I use excellent technical skills in either format, what will I gain by shooting 8x10? In other words, will a 60x75 inch print (landscape) from an 8x10 look THAT much better or different and how so?

I understand well how 8x10 film stores more data, but I'm particularly curious whether prints at the above size will look that much different if I use the best lens I can.

Thank you in advance for your input.

PS. I want to stay away from 5x7 due to my aspect ratio preferences.

[Jim MacKenzie]

Note that a 150mm lens on 4x5 will be much less wide than a 150mm on 8x10. You probably want a 300mm lens on 8x10 to keep the same angle of view.

If you're not experienced with large format, 4x5 will be far easier to get used to. It's also a lot more portable. Film is also much more available, with many more emulsion options. Lenses are easier to find.

"High quality" means different things to different people. I can get what I believe are quality 11x14s out of 35mm, if I use a tripod and slower film. That implies I could get approximately 44x56 prints out of 4x5. 5x7 would let you get about 55x70 which is very close to your requirement. Then again, with a print that size your viewing distance might be much more comfortable than I am thinking of with a 35mm to 11x14 print.

[Drew Wiley]

This is all relative. Do you own a drum scanner or paying someone else? (8X10 drum scans are a lot more expensive than 4x5's). What is your intended output - inkjet or Lightjet? (inkjet can't resolve as much detail). How closely do you expect
people to view your prints? And it's not like you can just pick up a large format
camera and instantly know what you are doing. In general, 4x5 is a easier and
certainly less expensive to learn, but if you want the most hypothetical detail, 8x10
is the way to go, PROVIDED you don't encounter major depth-of-field issues. The
same angle of view with a 4x5 exposure at f/32 will require f/64 with an 8x10,
hence a four times longer exposure PLUS reciprocity correction with most films.
Either way, anything printed digitally this big is going to have some real compromises.

[Archphoto]

Some basic's : lenses 35mm to 4x5 = factor 3, 35mm to 8x10 = factor 6
So, a standard 50mm on 35mm equals 150mm on 4x5 and a 300mm on 8x10.

Price-wise: 8x10 is a lot more expensive than 4x5: gear, lenses, film.

At 4x5 you are looking at a 15x enlargement, at 8x10 a 7.5 enlargment.
YES you will see a diference, up close, but I doubt at viewing distance if you use the finest grain film posible.
Think of Velvia 50 ASA for color.
And why should grain be an obstacle ?
Don"t forget that you will be dependable of the quality of your lab too, whether it is with 4x5 or 8x10.

I have both formats and had 30x36 prints of 4x5 at a regular basis and loved it, my customers, architects, too.

I would choose 4x5, esp if you are a newbe to LF and see if you like it at all.
4x5 is heavy, 8x10 is a lot more heavy: the camera, the lenses, the filmholders, the tripod and so on.

As far as lens quality: the Schneiders and the Rodenstocks have the same quality and there are very good Nikons and Fuji's aswell.

Peter

[e2aa]

Drew,

Thank you for your response. My answers to your questions/comments:

- I have access to a friend's drum scanner where 8x10 or 4x5 will cost the same.
- Lightjet, as most fine art photographers use these days for extra large prints.
- Longer exposures are no problem with my subject matter.
- I can address reciprocity correction issues in PS.

How would you print this large?

[e2aa]

Looks like I probably need 8x10.

Thanks everyone.

[Gem Singer]

Purchase the 4X5 film camera. Use a Schneider 150 Super Symmar-HM lens. Drum scan the color film. Edit in Photoshop. Print digitally with either a Lightjet or a wide frame inkjet printer.

You should have no trouble obtaining beautiful 60X75 inch prints, that are sharp and grain free, with a combination of those elements.

Whether large color prints that are made from scanned film capture are superior to prints that are made from high-end digital capture is a matter of personal preference.

[QT Luong]

This is all relative. Do you own a drum scanner or paying someone else? (8X10 drum scans are a lot more expensive than 4x5's). What is your intended output - inkjet or Lightjet? (inkjet can't resolve as much detail).

Actually, in my experience, labs charge by file size rather than capture medium, and inkjet prints are sharper than lightjets.

To answer the original question, of course 8x10 would be better, but I think 4x5 would be enough. For a print that large, a 15x enlargement is going to be acceptable to most.

[Drew Wiley]

Well, 8x10 is certainly rewarding. And Lightjet will squeeze the detail out fairly well.
I'm sure you'll pick a good lens. But the weak link is the filmholder. If you point the
camera down, the sheet will bow more than with a 4x5, so will not be in consistent
focus, at least for really big enlargements. I personally use adhesive filmholders
which solve this problem. You can get them from Sinar or potentially make them
yourself. Since I am a darkroom printer, you probably understand your workflow
past the film exposure stage much better than I would. In this day and age, Lightjet
will probably be the most direct way to achieve high detail. True optical prints can
be distinctly sharper, but the skill set required to do this is getting rare these days.
I only print my own shots, so don't have to deal with either compromises or tight
delivery schedules. 8X10 can also be a lot of fun, but the expense of it will certainly
self-regulate any waste of film!

[Drew Wiley]

QT- just curious, but where on earth are you obtaining inkjets sharper than Lightjet
from large format files? (or alternately, from Chromira, which is admittedly a bit
"grainy" even if sharper still). But at a 15x enlargement, how can ANYTHING be
considered sharp?? After all, I'm one of those folks who completely rejects the
"normal viewing distance" doctrine. A thirty-foot wide billboard made from 35mm film looks sharp from a "normal viewing distance" of 75 yards!

[QT Luong]

> where on earth are you obtaining inkjets sharper than Lightjet
from large format files?

Right out of my studio. The lightjets were from Calypso and WCI.

[don mills]

Regarding the OP's questions/requirements, 8x10 may yield creamier results at long exposures. 360mm lens is good.

Many fine artists today are using MF digital backs on their LF equipment to obtain great depth and tonality. The digital LF lenses today are outstanding.

Those on the cusp seem to experimenting with digital and software.

[don mills]

Yes, I know many also who are getting great results from new Inkjet printers. Superb!

QT, how large are you printing?



> where on earth are you obtaining inkjets sharper than Lightjet
from large format files?

Right out of my studio. The lightjets were from Calypso and WCI.

[Ivan J. Eberle]

OP's already been satisfactorily shooting 5 second exposures on digital sensors and stitching, albeit the workflow is slow? Realize that bumping up the format size and switching to film, he/she will now encounter reciprocity failure in addition to working at lower ISOs, smaller apertures. Captures that were a series of 5 second exposures could suddenly and easily run to many minutes in 4x5, perhaps an hour or more in 8x10.

Already has a MF digital back (and necessary pano equipment, presumably). Digitally optimized lenses at small focal lengths present great opportunities for extreme resolution. Perfect scenario to recommend sucking it up and dealing with the pain of stitching panos in Photoshop versus shooting film.

[Ron Marshall]

You might consider an 8x10 camera that has the option of a 4x5 reducing back; that way you can do test prints of an image from both formats and decide for yourself.

[Drew Wiley]

QT - right out of your studio? Well, home-cookin' is always the best! The sharpest
digital prints I have ever personally seen were some 20x24 lightjets printed on Fuji
supergloss, and were actually being falsely sold as Ilfochromes! The polyester stock
could certainly fool people if they didn't look closely. I didn't take the
photographer to task because he probably didn't know the difference himself, and was providing his clients with a superior product at a reasonable price. But comparing apples to apples, I've never seen an optical enlargement equal a good
home-cooked one either! Amazing where this is all going. The last time I visited
Ctein he was printing the same batch of portraits on inkjet side by side with dye transfers for a British museum. These were all MF shots so not extremely detailed, but as far as gamut is concerned, about 60% of the inkjets were equal in quality
to the DT, or nearly indistinguishable! (The other 40% - well that's a whole other
story!)

[Ivan J. Eberle]

OP specified 60x75", non-negotiable. Every spec I've ever seen or heard on LightJet printers says they're limited to a maximum width of 50".

While LightJets don't win in absolute resolution-- it's fixed at an input resolution of 304.5 dpi-- what they do have going for them is they're essentially big film recorders that use wet-chemistry darkroom papers like Fuji Crystal Archive. (Which means no potential for later outgassing as with inkjets).

[Drew Wiley]

Ivan - as far as resolution is concerned, straight optical printing would win hands-down direct from 8x10 film. Could be either negative or chrome, depending on the
paper type. Long exposures are not a problem with chromes like Astia or dupe films
under tungsten lighting. But optical printing is a different skill set with different
equipment, and this is a pretty big paper size. Fuji Crystal Archive directly printed from a relatively saturated negative like Provia VC would be a little on the soft side
at this degree of enlargement, so in this case, looks like inkjet might indeed be the only commonly available option. The last guy around here that made Cibas that big
has retired, and ruined his lungs long before by having 200 gallons of that damn
bleach in his lab! Nowadays we save our own lungs and poison people in other
countries with our hi-tech recyling!

[venchka]

Drew,

Thank you for your response. My answers to your questions/comments:

- I have access to a friend's drum scanner where 8x10 or 4x5 will cost the same.
- Lightjet, as most fine art photographers use these days for extra large prints.
- Longer exposures are no problem with my subject matter.
- I can address reciprocity correction issues in PS.
How would you print this large?

Shakes his head..........

One more person who thinks that bad exposure can be fixed in Photoshop.

[Ben Syverson]

Any "process" lens made since 1950 on 8x10 combined with good technique will give you wonderful gigantic exhibition prints. There's no magic bullet.

It doesn't have to be expensive either. A B&J 8x10 just sold in the For Sale section for $120. Combine that with a cheap process lens in the 300mm range. Since you're working in the field, I'd choose a f/9 Copal 1 lens over a f/5.6 Copal 3 boat anchor. Spend no more than $600 on the lens, and do not spend too any time trying to find the "best" lens. Leave that to the DSLR crowd -- any old process lenses will give you the sharpness you need.

Shoot at f/11, f/16 or f/22 instead of f/64, so you're not needlessly throwing away resolution. That will give you faster shutter speeds, which means you don't have to worry about wind and stability as much. Hopefully you can use tilt to give you the DOF you need. Otherwise, since it sounds like you're comfortable with Photoshop, you can do what Crewdson does: shoot multiple sheets of the same subject, each focused at a different point, and PS them together.

Portra 160NC will give you the best results in C41. In E6 I like Astia, but even that is too contrasty for me. C41 gives you the most options once you get into Photoshop. Any theoretical sharpness difference between C41 and E6 will be erased due to limitations of the scanner.

You will be forced into inkjet because no one (that I know of) can do 60x75" digital C prints. The machines just aren't that big. But that's fine -- honestly, if there is any sharpness difference one way or the other between inkjet and lightjet, you won't see it at 60x75. No one looks at exhibition prints through loupes.

[e2aa]

You missed the point. With extra long exposures where bright artificial light is present in a small section of the image, over exposure is inevitable. I'll have to link an example.



Shakes his head..........

One more person who thinks that bad exposure can be fixed in Photoshop.

[Drew Wiley]

Well, I just caught myself with my foot in my mouth, since Astia is now seemingly
impossible to get in 8x10. But I have also often used E100G for long exposures under dim lighting with no problem other than a time correction. Have also used Portra films, so even at f/64 with an 8x10, film itself isn't the issue for stationary subjects. But as already noted, the film does have to be correctly exposed in the first place!

[venchka]

A. You didn't mention bright artificial lights.

B. As Drew stated "the film does have to be correctly exposed in the first place!"

C. Do let us know where we will be able to see this ginormous prints.

[Ivan J. Eberle]

I say it'll doubtless prove easier to shoot 20x24" on three sheets of B&W film and make a tricolor Carbro print-- than it will be to get an answer that satisfies all of these conditions that seem destined (perhaps designed?) to prove the original workflow of MF digital back and stitching was superior to film for such night photography.

Yup, I said night photography. 5 seconds on a digital back @ --what?-- probably f/8 and likely no further stopped down than f/11, at ISO 400, likely as not. So what's that 5 or 6 stops further stopped down equate to in seconds at f/64 on 8x10? 160 seconds (5 stops) or 320 seconds (6 stops) on ISO 400, whoops make that ISO 50 (-3 stops is 1280 seconds --21 minutes:20 seconds or 42m:40s) -- before even factoring in reciprocity failure? Ha! If it wasn't completely dark to begin with, by now it will be...

Anyone else suspect we're being toyed with? This is the 4th post now from an enonymous rather than eponymous poster...

[Ben Syverson]

Anyone else suspect we're being toyed with?
Re-reading the original post, I have to say I'm starting to agree. In what universe is stitching a few frames of MF digital MORE work than shooting, developing, scanning and dustbusting 8x10?

[QT Luong]

.
You will be forced into inkjet because no one (that I know of) can do 60x75" digital C prints. The machines just aren't that big..

The Lightjets commonly installed are indeed limited to 50" rolls, but there is a machine called the Lightjet XL that can take 76".

[bglick]

It seems hard to fathom, if your subject matter can handle 4 second exposures, then its pretty damn still.... in which case, why mess with all this large gear, stitch, stitch, stitch....

As for printing, high quality ink jets can produce about 2x the resolution on paper than Light Jets...this assumes the original file has this much data to to print...and there is also some efficiency losses. IMO, LJ's are outdated already... hopefully the new crop of LED printers will print at 2x the rez the current crop offer. Jobo is first with 400 dpi, but small widths...

[QT Luong]

QT, how large are you printing?

Anywhere between 18" and 90", with 45" being my favored size.

[Bruce Watson]

QT- just curious, but where on earth are you obtaining inkjets sharper than Lightjet from large format files? (or alternately, from Chromira, which is admittedly a bit "grainy" even if sharper still).

This topic has been discussed here at length more than once. Search the site, you'll find it I'm sure.

To summarize, the majority opinion was that inkjets are the sharpest print medium currently available. So it's not just QT who thinks this.

[Ivan J. Eberle]

Good to know there are LightJets out there that print this big. (I happen to think C prints are great because the media is so comparatively cheap). As a practical matter, since we're not talking about analyzing satellite images of missile silos, 304.5 DPI resolution of a LJ oughta be sufficient resolution for a 60"x75" print. Especially since the OP specified an upper limit of 8x10. Whether it's possible to noticeably improve upon a 2283 dpi image file needed for a LJ from a 8x10 sheet of film (color negative, given this new high DR requirement), so that the higher potential res of an inkjet means anything, seems questionable.

[bglick]

> To summarize, the majority opinion was that inkjets are the sharpest print medium currently available. So it's not just QT who thinks this.


In digital, yes....but optical prints still beat the pants off everything, as the the best darkroom papers can hold about 3x what inkjet paper can hold... of course, the limit is often in the original.... and....

the ink jets are already holding enough detail to be at the eye limit, for a 20/20 person at about 15"....so clearly diminishing returns in most cases...

[Ben Syverson]

the ink jets are already holding enough detail to be at the eye limit, for a 20/20 person at about 15"....so clearly diminishing returns in most cases...
Such as a 60x75" print at any reasonable distance

[bglick]

> Such as a 60x75" print at any reasonable distance


gotta work out the numbers....

10 lp/mm on the print, add in some efficiency losses in the printing process, so

13 lp/mm fed to printer, * 2 * 25.4 * 75 = 50k resolvable pixels

A low DOF shot, either infinity or a 2d plane, can yield about 40 lp/mm on color chrome film, about 30 lp/mm on color neg.

Using color neg

30 *2 * 254 = 15k resolvable pixels

so about 1/3 short of the 10 lp/mm goal to paper...

However, with a long DOF shot, say f64, you will fall below half of this, 1/8 th the max. paper can hold..... (this is the finest glossy ink jet paper, not rag)

But much of this is subjective, as view distance and visual acuity of the observer is the variables that can make or break your goals.... Example, using 20/20 vision, (1 arc minute), the eye limit is at 60 pixels per degree. (pixel = line = dot, etc.)


So at 10" print view distance, one degree = 4.5mm of horizontal print. (simple trig). In which case, 60 resolvable pixels would be the eye limit. (20/20)

In 75", we have 15k pixels / (75*25.4) = 7.9 pixels per mm * 4.5 = 35 pixels, which is about half the eye limit.

But if you push the view distance to 20" (more reasonable, as only kids can focus at 10"), you are at 70 pixels per degree, a bit above the eye limit.

Of course, you can keep tweaking the numbers... if a person has 20/10 vision, at 20" he will see half his eye limit. If a person has 20/40 vision at 20" he will see 2x his eye limit.... as you can see, lots of variables to consider... its best to reverse engineer from your final goal on the final product and take into consideration the avg. visual acuity of the observer.

If you really want to get deeper....next you have contrast and brightness issues. If the print is low contrast, the avg. person can no longer resolve 20/20. But if its a high contrast AND VERY well lit, a persons visual acuity improves, specially if the eye pupil diam. has been driven down to 3mm diam. or smaller, in which case, you need a to increase the resolution on the target to achieve the eye limit... and if the print is a very strong back lit trannie, the eye can resolve double, vs. front lit.... (20/10) But remember, many older people like myself still have excellent visual acuity, 20/13 for me, but Myopia has rid my ability to close focus, so 10" would be an absurd distance to consider, unless everyone over the age of 35 brings their reading glasses to the exhibit...

Keep in mind, this was all done with an example with a very SHALLOW DOF image where you can shoot a killer lens, such as the 150mm SSXL at f11 or a normal lens at f16. But at f64, all these numbers crumble... this is why DOF is 810's nemesis...

Anyway, this should give you a feel for where you need to be at....

confused yet?

[e2aa]

I find this whole DOF issue confusing. Probably b/c I have no experience with large format film.

On one hand, many 4x5 shooters on here seem to complain about 8x10 DOF. On the other hand, most fine art photographers seem to like the DOF and tonality of 8x10.

[e2aa]

Being toyed with? Don't kid yourself.

You underestimate the MF digital stitching process.

If you are up for the challenge, rent a P45+/P40+/P65+ with a Cambo Digital Wide DS and go through the process to get the 4-6 files required for a stitched image that would result in a print similar to a single 8x10 image (60x75). Only after you import to PS (or whatever software you can get) and actually attempt to stitch the 4-6 frames together will you experience my frustration. I guarantee you this is as tedious as anything and the exposures will be very tricky to blend. It will take you hours to get the image looking as you want, if you are lucky. You may have to go take more shots.

The appeal of 4x5 or 8x10 to me is (1) ability to see the entire image on the ground glass before capture and (2) only having one file to deal with in PS.

I know I am naive about LF film as a medium. And I know there are many trade offs. Don't you see that is why I am on here asking questions and wanting to try for myself? I can accept that 4x5/8x10 is difficult and time consuming in its own ways, and more so in general, than MF digital...maybe I will sell the 8x10 after I try, maybe not.

In a few years, after Phase One has produced a p85+++ that produces a file from one shot that equals 8x10, then I will forget about film.




Re-reading the original post, I have to say I'm starting to agree. In what universe is stitching a few frames of MF digital MORE work than shooting, developing, scanning and dustbusting 8x10?

[bglick]

> On one hand, many 4x5 shooters on here seem to complain about 8x10 DOF. On the other hand, most fine art photographers seem to like the DOF and tonality of 8x10.


for the non technical photographer, this can be confusing.... in a nut shell, it comes down to aperture diffraction, i.e. the higher the f stop, the lower the aerial lens resolution, hence the lower the recorded resolution on film. Jumping up 2x in a format size, requires double the f stop to achieve the same DOF.... which means, the same composure and the same resolution on the same final size print. Now, this effect varies between formats, I will try to summarize....

For considerable DOF shots... such as
35mm f8,
MF f16,
4x5 f32,
8x10 f64.

35mm to MF..... very marginal loss (nature of short fl lenses)...this means even with relatively long DOF, MF will come close to 2x the recorded resolution.

MF to 45 ...... significant loss, resolution gain down to about 1.5x

45 to 810 ...... very significant loss, resolution gain down to 1.3x

Now, if there is shallow DOF, or no DOF, such as infinity or 2d plane (brick wall mural), then each jump up on format will provide about 1.8x the resolution as the previous format.

This is why you should pick your formats carefully.... sometimes bigger is only marginally better. However, there is other things to consider such as film type and film grain, as well as enlargement factor. In this digital age, if the film is scanned, grain is less of an issue today vs. when film was optically enlarged for a print.... grain removal software does an excellent job.....

That's as simplified as I can make it...

Now you see the value of stitching.... assuming the subject is cooperative, it can't be beat.... the digital post processing tools today are amazing... the capture can be digital or film, it doesn't matter...

[bglick]

out of curiosity, why such problems stitching a few P1 MF shots together?

[rdenney]

I find this whole DOF issue confusing. Probably b/c I have no experience with large format film.

On one hand, many 4x5 shooters on here seem to complain about 8x10 DOF. On the other hand, most fine art photographers seem to like the DOF and tonality of 8x10.

The larger the format, the less the depth of field at a given aperture. Those fine-art photographers make use of 8x10's lack of depth of field, which can produce effects just not possible with smaller cameras. But if it's a uniformly sharp image you want, you have to stop down considerably to recover the depth of field lost by going to the larger format, and that smaller aperture allows diffraction to creep in. Diffraction causes a loss of acutance, but so does not being in focus. Not being in focus is usually worse than diffraction, but prints of the size you are considering viewed up close really put any loss of sharpness on display.

If we work from 5 lines/mm as the target resolution (a sharply resolved print viewed without a magnifying glass at 10 inches), we'll need at least 10 pixels/mm to make those lines, and more if they are diagonal. Your 75" print needs 250 pixels/inch, or 18750 pixels in the height of the image. That's close to my own experience with Epson prints, where the visual differences between a print at 240 pixels/inch and higher pixel densities are subtle indeed--I need a magnifying glass to see them.

An Epson flatbed scanner will give you about 10,000 pixels from the long dimensions of 4x5 at the limit of its capability--not enough for such a print. The 8x10 will give you about 20,000 pixels, and that is enough for your print.

The enlargement of the 8x10 will be 7.5x. 7.5 times those 5 lines/mm is 37.5 lines/mm that need to be present on the film. If they aren't, then the pixel resolution may be fine but the optical resolution won't be. With 4x5, the enlargement is 15x, which will require 75 lines/mm from the lens. Large-format lenses will only deliver that at optimal aperture and exactly on the plane of sharp focus. Depth of field doesn't mean more stuff is in focus, it just means more stuff appears to be in focus. The larger the print, the more exacting are the standards for depth of field.

DOFMaster uses a point standard of sharpness (characterized by the circle of confusion) of 0.2mm for 8x10, but that's based on the assumption of a 10" print. At 75 inches, it should be divided by 7.5, which is .026mm, or something like 1/1000". With 8x10 focused at 10 feet, the depth of field will be 0.35 feet at f/22--not much. F/22 is probably the sweet spot for the typical 300mm normal lens for 8x10. Focused at 100 feet, the depth of field extends from 84 feet to 124 feet--again, not much.

For 4x5, the standard of sharpness based on a 10" print is 0.1 mm. At 75 inches, in should be 0.013mm, or around 1/2000". With 4x5's 150mm normal lens focused at 10 feet, the depth of field at f/22 will be 0.74 feet, twice what it is for 8x10. Focused at 100 feet, the depth of field is 91 feet, more than twice the 40 feet that it is for 8x10. So, with the same exposure and the same standard of sharpness for the final print, which is dictated by the visual acuity of a person with good eyesight viewing the print from 10 inches away, the 4x5 will have more depth of field and thus more of the scene will be in apparent sharp focus.

With the 8x10, the only solution would be to stop the lens down to f/45, requiring four times as long an exposure. That's why your 5-second exposures will be 80 seconds for 4x5 (assuming you were getting away with f/11 on medium format) and 1280 seconds on 8x10, plus the effects of reciprocity, in order to get the same basic image.

But f/45 will show more diffraction than f/22, and that will undermine the lens resolution across the board, and the image will not hold up to close scrutiny because of that.

So, we have competing causes of inadequacy:

1. The image can be undermined by too few pixels.
2. The image can be undermined by enlarging beyond the lens's optical capabilities.
3. The image can be undermined by insufficient depth of field to render those scene elements in apparent sharpness that need to appear sharp.
4. The image can be undermined by diffraction caused by too small an aperture.

What you are are seeking is a dynamic balance between these competing influences. If you can photograph your subject with the depth of field allowed by 8x10 and a practical shutter speed and optimal aperture, then that is the format that will not require more than lenses can deliver or more than a reasonable scanner can deliver.

But if 8x10 doesn't provide sufficient depth of field for your subject, then parts of your subject will either be out of focus or the aperture you'll need to get them in focus (if it's even available on the lens) will cause visible enough diffraction to become the limiting factor in achieving your print size. You might be able to solve the problem using 4x5, and going to a higher level of scanning to achieve the number of pixels you need. You'll also need good lenses used carefully.

Medium format would require very high-end scanning (or capture) to obtain a sufficient number of pixels, else that would constrain the final image. Also, the degree of enlargement would require more than lenses can deliver, even at their sweet spot.

If you can relax the viewing distance requirement and thus the standard of sharpness, it all gets easier. But at this point, it mainly depends on your subject and the required depth of field. (Of course, one of the main benefits of a view camera is the ability to tilt the focus plane usefully, and this can often solve a focus problem without increasing depth of field.)

Not present in my discussion is the tonality issue. Larger formats most assuredly have better tonality, but while this is a subtle effect of great importance to many fine-art photographers, I'm not sure a reasonable solution space doesn't already cover all your options.

As with all system decisions, it comes down to understanding your requirements first.

By the way, DOFMaster is quite useful for calculating depth of field. At your print size, however, you need a much stricter standard than it uses--choose your own circle of confusion, following my calculations above.

Rick "offering the same reasoning as others in different words in case it helps" Denney

[bglick]

> An Epson flatbed scanner will give you about 10,000 pixels from the long dimensions of 4x5 at the limit of its capability


You are dealing with marketing information, not hardcore data... Epson scanners must over scan by a factor of several times after exceeding about a 6x enlargement factor. A $400 scanner will not match the performance of a $40k scanner....the sad reality of the equipment in our field....





> With 4x5, the enlargement is 15x, which will require 75 lines/mm from the lens. Large-format lenses will only deliver that at optimal aperture and exactly on the plane of sharp focus.


You are confusing aerial resolution vs. recorded resolution.... assuming color film....




> F/22 is probably the sweet spot for the typical 300mm normal lens for 8x10.


f32 is much more commonplace, at least with all the MTF data I have looked at....





> So, with the same exposure and the same standard of sharpness for the final print, which is dictated by the visual acuity of a person with good eyesight viewing the print from 10 inches away, the 4x5 will have more depth of field and thus more of the scene will be in apparent sharp focus.



The reality is, DOF does not change with format. This assumes same composure, same sharpness at the near / far for the equal size final prints. When you double the format size, you double the fl, since enlargement will be 1/2 with the larger format (vs. the smaller format) you half the cc to compensate for the reduced enlargement factor. You will end up with the same Hyperfocal distance for both formats. F stop and cc are inversely proportional to each other in the DOF equation.


There is two benefits of larger format as it relates to DOF... the first is the center of the image will be sharper.... as DOF represents the min sharpness of the near and far points only. Secondly, less grain in the larger format and often better tonality...


Of course, there is some major drawbacks in larger formats as well.... each time you double the format, you loose two stops of shutter speed... this makes the capture more sensitive to motion and camera vibrations, which both can further reduce resolution. The larger the camera, the more sensitive it can be to noises, wind, etc.




>But f/45 will show more diffraction than f/22, and that will undermine the lens resolution across the board, and the image will not hold up to close scrutiny because of that.


See my comments above.... this is self correcting...





> But if 8x10 doesn't provide sufficient depth of field for your subject, then parts of your subject will either be out of focus or the aperture you'll need to get them in focus (if it's even available on the lens) will cause visible enough diffraction to become the limiting factor in achieving your print size. You might be able to solve the problem using 4x5, and going to a higher level of scanning to achieve the number of pixels you need.



other than grain, you will end up in the same place, see my comments above. The limitation here is the amount of resolution recorded at capture... scanning at a higher resolution will not create more resolution in the film.....


/

[rdenney]

>You are dealing with marketing information, not hardcore data... Epson scanners must over scan by a factor of several times after exceeding about a 6x enlargement factor. A $400 scanner will not match the performance of a $40k scanner....the sad reality of the equipment in our field....

With all due respect, I'm dealing with the results I get scanning my own 4x5 negatives in my own V750. And I compare those results with the 6x7 scans from my Nikon 8000ED for which I paid four times as much, which also provides about 10,000 pixels at similar pixel quality from 6x7 (using the glass carrier).

Many, many testers have concluded that the Epson flatbeds are good to about 2000 pixels/inch if used carefully, and my results do not refute those claims.

I did not say that the pixels would not be sharper with a drum scan, but they are sharp enough to do what I said they would do. I can make basic corrective sharpening in Photoshop with a radius of 0.9 or 1.0 pixels with scans at 2400 pixels/inch. That would not be possible if there were no resolvable edges at the pixel level.

And I don't know where you priced a V750, but I wish I'd only paid $400 for mine.:)

I did say, that if he wants 20,000 pixels from smaller than 8x10, he's going to have to upgrade his scanning capability beyond what is possible with an Epson flatbed.


You are confusing aerial resolution vs. recorded resolution.... assuming color film....

But that does not undermine the principles being discussed or the conclusions. And the OP clearly didn't catch all of what you said, because he asked a question central to your explanation. I thought a different way of describing it might help.

You'll notice that I converted those decimal representation to fractional representation with one significant figure. These are approximations intended to demonstrate the effect and the underlying principles. Without knowing the OP's specific requirements, the numbers are just not much help: Too much precision in pursuit of too little relevance.

Rick "noting that we came to basically the same conclusion by somewhat different paths" Denney

[Ivan J. Eberle]

out of curiosity, why such problems stitching a few P1 MF shots together?

Because it's more fun to wind us up and let us go?

[el french]

Because it's more fun to wind us up and let us go?

And Photoshop is one of the poorest stitchers on the market. I use Microsoft ICE for 99% of my stitches and PTAssembler when I want more control of the stitching process.

[bglick]

what version PS has a poor stitching operation? I found CS4 very effective?

[venchka]

Perfect! Go for it! By all means share your results. I for one am eager to see your monumental prints. I hope they will be displayed in North America.

I was wondering if you had considered 6x12 or 6x17 roll film? Either scanning and printing individual frames or stiching pairs together horizontally.

Good luck!


Being toyed with? Don't kid yourself.

You underestimate the MF digital stitching process.

If you are up for the challenge, rent a P45+/P40+/P65+ with a Cambo Digital Wide DS and go through the process to get the 4-6 files required for a stitched image that would result in a print similar to a single 8x10 image (60x75). Only after you import to PS (or whatever software you can get) and actually attempt to stitch the 4-6 frames together will you experience my frustration. I guarantee you this is as tedious as anything and the exposures will be very tricky to blend. It will take you hours to get the image looking as you want, if you are lucky. You may have to go take more shots.

The appeal of 4x5 or 8x10 to me is (1) ability to see the entire image on the ground glass before capture and (2) only having one file to deal with in PS.

I know I am naive about LF film as a medium. And I know there are many trade offs. Don't you see that is why I am on here asking questions and wanting to try for myself? I can accept that 4x5/8x10 is difficult and time consuming in its own ways, and more so in general, than MF digital...maybe I will sell the 8x10 after I try, maybe not.

In a few years, after Phase One has produced a p85+++ that produces a file from one shot that equals 8x10, then I will forget about film.

[e2aa]

Very helpful explanation, thanks.




> On one hand, many 4x5 shooters on here seem to complain about 8x10 DOF. On the other hand, most fine art photographers seem to like the DOF and tonality of 8x10.


for the non technical photographer, this can be confusing.... in a nut shell, it comes down to aperture diffraction, i.e. the higher the f stop, the lower the aerial lens resolution, hence the lower the recorded resolution on film. Jumping up 2x in a format size, requires double the f stop to achieve the same DOF.... which means, the same composure and the same resolution on the same final size print. Now, this effect varies between formats, I will try to summarize....

For considerable DOF shots... such as
35mm f8,
MF f16,
4x5 f32,
8x10 f64.

35mm to MF..... very marginal loss (nature of short fl lenses)...this means even with relatively long DOF, MF will come close to 2x the recorded resolution.

MF to 45 ...... significant loss, resolution gain down to about 1.5x

45 to 810 ...... very significant loss, resolution gain down to 1.3x

Now, if there is shallow DOF, or no DOF, such as infinity or 2d plane (brick wall mural), then each jump up on format will provide about 1.8x the resolution as the previous format.

This is why you should pick your formats carefully.... sometimes bigger is only marginally better. However, there is other things to consider such as film type and film grain, as well as enlargement factor. In this digital age, if the film is scanned, grain is less of an issue today vs. when film was optically enlarged for a print.... grain removal software does an excellent job.....

That's as simplified as I can make it...

Now you see the value of stitching.... assuming the subject is cooperative, it can't be beat.... the digital post processing tools today are amazing... the capture can be digital or film, it doesn't matter...

[Ben Syverson]

So at 10" print view distance, one degree = 4.5mm of horizontal print. (simple trig).
Are you trying to be funny? 10" is not a reasonable viewing distance for a 6.25 x 5' print. Neither is 20".

Reasonable is 60".

[Jeff Keller]

A handy diffraction calculator is at the bottom of:
http://www.cambridgeincolour.com/tutorials/diffraction-photography.htm

A 75" print created from a 4x5 viewed at 1m will start to diffraction limit at f16. (An 8x10 at f32)

The 15x enlargement viewed at 1m would show similar detail as viewing a 15" x 22" print from a 35mm camera at 1m. If you really want an image that stands out as being sharp, you probably want to think about the 8x10.

Jeff Keller

[Carsten Wolff]

...in other words: Get a 5x7 camera and any modern 210mm offering (Sironar-S, if you must).....with that set-up you can add a 4x5 reduction back and a 6x17 back as well. I even managed to get a Canham 617 back on an old Arca 5x7, by making a simple 5x7 Graflok type back for it. :) choice of film emulsions is not that high, but its enough.

[venchka]

Carston makes a point that crossed my mind as well. The OP stated that 5x7 was out for aspect ratio purposes. However, lurking within the confines of a 5x7 negative, or positive, is an infinite number of 4x5 images. In case you got the framing a bit off. Also there is a 5x6 image on the 5x7 negative. 5x6 = 4x5 aspect ratio only bigger. 50% bigger. 30 sq. in. versus 20 sq. in. Before enlarging.

Add the 6x17 benefit and 5x7 starts to look attractive. Add the 5x7 aspect ratio and 5x7 looks very very attractive.

Film selection is the downside.

[bglick]

> Are you trying to be funny? 10" is not a reasonable viewing distance for a 6.25 x 5' print. Neither is 20". Reasonable is 60".



If everyone viewed prints at their diagonal distance, we could all shoot 35mm film..... No reason for more IQ. If you follow many of these posts, they mention how they want the print to stand up to close scrutiny, as so many people walk right up to a 80" print. I never suggested 10" is reasonable.....(that was you suggested it) I provided the math so you can back-up the person to any distance that satisfies your requirements, get it? It doesn't get any easier....



> A 75" print created from a 4x5 viewed at 1m will start to diffraction limit at f16. (An 8x10 at f32)


And this does not take into account the viewing conditions, the viewers acuity and most importantly printing efficiency losses.... So it only gets worse, not better vs. what the calc. spews out...

[rdenney]

If you are up for the challenge, rent a P45+/P40+/P65+ with a Cambo Digital Wide DS and go through the process to get the 4-6 files required for a stitched image that would result in a print similar to a single 8x10 image (60x75). Only after you import to PS (or whatever software you can get) and actually attempt to stitch the 4-6 frames together will you experience my frustration. I guarantee you this is as tedious as anything and the exposures will be very tricky to blend. It will take you hours to get the image looking as you want, if you are lucky. You may have to go take more shots.

Question for the assembled masses: Is there a sliding back to fit an 8x10 camera that would allow one to make images for stitching with a P-whatever back? That would address all the issues the OP brings up above:

1. The vignetting pattern on the lens would be even across all the stitches.

2. There would be no possibility of parallax error.

3. The stitches would not be complicated by even slight geometric distortion in the lens.

4. The stitches would not be complicated by any variation in sharpness across the frame.

5. The OP would be able to compose the whole image at once.

What makes stitching images made from a repositioned camera difficult is geometric distortion, vignetting, mismatched sharpness at the edges, perspective errors, and parallax errors. Sliding a medium-format digital back around on an 8x10 camera back would address those issues, it seems to me.

Rick "working the problem" Denney

[rdenney]

> Are you trying to be funny? 10" is not a reasonable viewing distance for a 6.25 x 5' print. Neither is 20". Reasonable is 60".

I disagree, on the basis that it depends on what the image is to be used for. The OP hasn't said what he's photographing (or maybe I missed it), but what if he is documenting, say, medieval tapestries? The objective for that is to record micro-detail as accurately as possible for later study, not to make a gallery image with a rope preventing people from moving up on the image.

But I also disagree with the assumption that people don't or shouldn't move up on the image. I bought a print recently that is 20x40 inches. One of the reasons I bought it is that even from a distance, it invited me to come close and be drawn into it. That effect would have been lost if upon coming close, the print's image quality broke down. That print looks very good from 10 inches, even though I have to choose a different porthole in my trifocals to focus on it. When I move in that close, the print almost entirely fills my peripheral vision, and it quite transports me to the place it pictures. That is the print that has brought me back to large-format work--I want my prints to be able to draw the viewer in without distracting him because the image breaks down on close scrutiny.

Rick "isn't this why we do large format?" Denney

[bglick]

The problem with MF digi back with LF is.... aerial resolutions of 810 lens are very poor vs. MF lenses. You also are contending with very large capture angles once you leave the center of the print, which no digital back handles very well...hence why digital lenses were designed, to work with the finnicky sensors....

In addition, it would never be as effective as taking an SLR and a proper pan head, and stitch the captures. The reason is, when you move to a stitching head, you now use normal to long fl's, which is EXACTLY what the sensor desires for best IQ.

Again, if the subjective is cooperative, digital stitching, even with a $999 Canon 50d can blow away 8x10 resolution, specially with a high DOF shot... sad, huh.... OH yeah, one other major benefit.... for the same final print rez/size, the stitched file will be about 1/2 the size of the scanned file.... and when file sizes are in the Gig range, this by itself makes stitching the logical choice.... its great to have so many options today, both at capture, and in post processing....

You can always bring a cheap 810 for composure only....But a cardboard cut out of the aspect ratio you desire, placed at specific distances from your eye (proposed fl) ... now, you see the image in proper orientation vs. upside down and backwards.... when you have time to prepare for a shot, the options are limitless...



Rick...

Originally Posted by bglick View Post
> Are you trying to be funny? 10" is not a reasonable viewing distance for a 6.25 x 5' print. Neither is 20". Reasonable is 60".


Just to be clear, benny posted this, not me, I only commented on it....

[Drew Wiley]

Apparently some of you mistake photographs for aerosol-can gang graffiti. I personally
put my nose right up to the print, reading glasses and all. And that's also how people
view my own prints. They love the detail, the precision. Beyond the overall composition, there's the discovery of a lot of detail. That's the whole advantage of
large format to begin with. I've said repeatedly, "normal viewing distance" is a bunch of bull unless you're into outdoor advertising. But apparently, the line separating
billboards from photographic "art" is becoming hopelessly blurred nowadays.

[bglick]

> But I also disagree with the assumption that people don't or shouldn't move up on the image.


Agreed.... in todays world, everything is scrutinized to death... and for some reason, walking up close to a 60" print is considered commonplace.... 20 years ago, it was considered absurd. The better the technology gets, the more people find ways to exploit it. It becomes a new benchmark of greatness for sharpness freaks...


But, all this resolution is never fully wasted. In Cteins first book he did an interesting experiment....he continually added more resolution to a set of prints, well above the eye limit. He is meticulous with his approach and is highly qualified in this regard. He made about 8 prints, up to 50 lp/mm... he found that people could place the prints in perfect order of sharpness, up to 30 lp/mm, which case the testers could not discern any differences. This demonstrated clearly, that although we may only resolve 1 arc minute (20/20), our ability to "discern" detail goes way above this. So a 75" print that can stand up to 15" viewing distance, will still provide added benefits at the normal viewing distance... specially for those with better than 20/20 vision.

[Jim collum]

you'd be able to do it with a 4x5, at least a 33mp MFDB and the Kapture Group's quad stitch http://www.kapturegroup.com/quad/quad.html (which is 'only' $5,000 for the sliding back alone)

with a 33Mp back, you'll end up with about an 18,000x14,000 pixel stitched image, which can be printed at your dimensions at about 240dpi (and since there's no alias filter on the DB, a print at 240 dpi won't show any digital 'artifacting' even at nose to print distance.

[bglick]

Jim, remember, native pixel count does not equal recorded resolution.... which is function of the sensors MTF and the lenses aerial resolution. In this case, since you are still forced to use a LF lens, diffraction is very limiting, so you can cut the recorded resolution to half of the native resolution.

this is the beauty of stitching with 35mm gear, shorter fl's, wider apt's and you do not subject the sensor to wide angle rays at the edges and corners. Each capture is working at the"design" conditions....

[Ben Syverson]

I disagree, on the basis that it depends on what the image is to be used for. The OP hasn't said what he's photographing (or maybe I missed it), but what if he is documenting, say, medieval tapestries? The objective for that is to record micro-detail as accurately as possible for later study, not to make a gallery image with a rope preventing people from moving up on the image.
Re-read the title of the thread. "Format for 60x75 inch Gallery Prints" says to me these prints are intended for a gallery setting, not academic study. Add to that this from the OP: "I shoot primarily 5-second (plus) exposures of landscapes and interiors (devoid of people) in color."

Personally, I think both MFD and 8x10 aren't what you want for ultra-large prints of immobile subjects. Get a GigaPan with a small DSLR, and make 3 gigapixel captures. Nothing else can come close.

[bglick]

> Personally, I think both MFD and 8x10 aren't what you want for ultra-large prints of immobile subjects. Get a GigaPan with a small DSLR, and make 3 gigapixel captures. Nothing else can come close.

Ditto, ditto, ditto....

[el french]

what version PS has a poor stitching operation? I found CS4 very effective?

CS4. I usually have a lot more than 3 0r 4 images and CS4 just isn't as accurate aligning the images as either ICE or PTAssembler. My success rate with CS4 was really low and it doesn't have any redeeming features that I could find when comparing it to either ICE or PTAssembler. PTAssembler has more output projections than any other stitcher, while ICE is very automated.

Here's a recent one done with ICE and Zerene Stacker: http://img.photobucket.com/albums/v649/etfrench/P7309376Fb.jpg

I'm not trying to hijack the thread, but I just wanted to point out that using CS4 as the stitcher may be the weak link in the workflow.

[bglick]

Interesting feedback, I only used CS4 for joining maybe 3 at a time... it was flawless, but as you say, its not a dedicated stitcher, so I am sure the other programs offer more in this regard... I guess the quality of the starting files will dictate how well the automated programs will do...