First Large Format (Ignorance and Expense)

[MattKing]

The Kodak materials use 8x the focal length as the threshold for when bellows extension exposure affects start to matter.
And there are/were ground glass metering systems for large format - Sinar offered a nice option that involved a probe, IIRC.

 

[tih]

And there are/were ground glass metering systems for large format - Sinar offered a nice option that involved a probe, IIRC.

Gossen had the PROFI-flex attachment for their PROFISIX (aka Luna-Pro) light meters.

 

[abruzzi]

So, what prevents one from taking your light meter and sticking it behind the ground glass? Seems like that'd give you an accurate reading, right? You'd have to make sure that your meter is pointing exactly where you want it, be a little more precise with where you aim but I don't see many reasons why that wouldn't work.

Some companies made metering backs that could directly meter at the film plane. Sinar made one--I don't know if it worked on the F2, but on the P and the P2 there was a metering back that had place to insert a metering wand. the wand would meter at the tip, so like a spot meter you could move the tip to different points in the scene and take readings. Also, Horseman made a meter that inserted like a film holder. I've never used one, but I assume it was more of averaging meter.

I think at this point, don't worry about bellows factor unless you're doing anything moderately close up. Just keep an eye on how far forward the lens is racked. A A 150mm lens focuses infinity at 6 inches, if you rack the lens forward another 3 inches, you are in 1 stop territory (tachincally you'll hit 1 stop a little before 3 inches). Until you get there, its best not to worry about it. You can do a similar calculation for whatever focal length--210 is a bit longer than 8 inches, so at 4 inches you'll hit 1 stop.

 

[John Patrick Garriga]

So, more general question but I think it applies here (I've never had to worry about this because I've never been using a camera with enough detail for this to be a factor). How big of a deal is light diffraction? I know it's a factor, but could I go to f/45 on my Schneider 210mm without worry? And, if it is, Unsharp Mask would be enough to fix it wouldn't it?

 

[Donald Qualls]

For an average large format lens (say a 150 mm) you'd have to stop down to f/64 before diffraction became significant -- and people actually did that, a lot, when Ansel Adams was young (there was an f/64 Group that he was a member of early on). You can readily demonstrate that on a 50 mm lens (for 35 mm film, which gets enlarged a lot more than large format), the diffraction loss at f/22, even f/32 is usually less than what you gain in depth of field if you have a scene that needs both near and far in focus (YouTuber Steven O'Nions actually posted a video about exactly this a few weeks ago). And since diffraction depends more on the physical size of the aperture than on the f/stop ratio, on a 150 mm lens you can be a stop and a half smaller that that (in the f/45 range) before it shows up, and then gain more by needing only about 1/3 as much magnification for a given print size -- so once again, we're looking at f/64 for 150 mm, likely f/90 on a 210 before you need to worry much about diffraction. Subject movement during a long exposure will be more of a problem by the time you're past f/45...

 

[Sirius Glass]

So, more general question but I think it applies here (I've never had to worry about this because I've never been using a camera with enough detail for this to be a factor). How big of a deal is light diffraction? I know it's a factor, but could I go to f/45 on my Schneider 210mm without worry? And, if it is, Unsharp Mask would be enough to fix it wouldn't it?

Usually the lens manufacturers set the minimum aperture a stop or two larger than when the diffusion starts to become a factor.

 

[DREW WILEY]

If I was still shooting 8X10 chrome film, now at around $40 per shot with processing, I don't think I'd want to gamble on any of the shoot from the hip closeup advice about bellows extension on this thread. I'd want to know the factor exactly. And that's the case even with color neg and black and white film. If you have along one of those basic little aid devices, like the Calumet one I mentioned earlier, it's so darn easy that why forego it.

Per when the effects of diffraction significantly sets in, as a rough rule of thumb, it starts becoming apparent in enlargements from 4x5 film anything smaller than f/32. For 8x10 film, around f/64 is the limit, or maybe even f/45, assuming film in your holder is actually being held flat, which it often isn't. Sometimes sloppy adjustment in one factor disguises carelessness in another; but it's still there, and all adds up.
A mask can't cure something inherent to the exposure itself. It can simulate a little more edge definition, but that takes some experience if doing it darkroom style. But it can't add fine detail lost to begin with due to excessive diffraction

I completely disagree with Donald. A 4x5 film shot using a 210 lens at f/90 is going to look downright mushy with any degree of enlargement. At f/45, I'd be scratching my head too. Even an 8x10 enlargement at f/90 and the equivalent angle of view will look conspicuously soft. Only contact printers with zero magnification in the print can routinely get away with very small stops, undetected.

 

[Donald Qualls]

@John Patrick Garriga While I'd say Drew is technically correct in what he writes, it's worth noting that he has a long history here of advising that any other than wavelength-level precision and perfection is unacceptable. I'd rephrase what he said above about sloppiness to mean that unless every single part of your equipment and process is perfect (and it isn't), you won't be able to tell diffraction from defocus at f/45 on a 150 mm lens (with 4x5 negatives, anyway).

If you follow Drew's advice, you might well give up before you actually expose and process any film.

Find out for yourself -- shoot the same scene at f/22, f/32, f/45, and f/64 (if your lens will stop down that far -- many won't even in large format focal lengths). Examine the resulting negatives with a loupe. Learn the difference between defocus and diffraction (hint: one is local and depending on distance to subject, the other is not). Then make your own decisions.

And of course, don't do your early learning at $40 a sheet for 8x10 chromes...

 

[abruzzi]

Aww, come on…there is nothing like chromes on large format. I’ve never done 8x10, but they are stunning on 4x5, if maybe a little expensive.

 

[DREW WILEY]

How many people ACTUALLY go around shooting 4X5 at f/90? I've never met one of those in my entire life, nor even using f/64 with film that size. Most are too paranoid to shoot any smaller than f/22. But by all means take Donald's own advice, and go out and find a cheap 2X loupe with fungus all over the lens, to help everything look the same when it actually isn't, and never will be.

All this applies to medium format and even 35mm shooting too. Who goes out and spends a ton of money for an allegedly super-crisp lens and then shoots it at a stop so small it degrades that very potential? Who does that? If it deliberately achieves some soft look you have in mind, fine; but don't pretend the effect isn't there. People figured that out 150 year ago.

 

[Alan Edward Klein]

Doesn't diffraction depend on the size of the print as well?

 

[Donald Qualls]

Aww, come on…there is nothing like chromes on large format. I’ve never done 8x10, but they are stunning on 4x5, if maybe a little expensive.

Oh, absolutely -- but do your early learning with Fomapan. Or FP4+, even. I've been shooting 9x12 and 4x5 since 2003, and just recently bought my first box each of Portra 160 and Ektachrome 100 sheets. I'm not really sure I'm ready for them even now (I don't shoot as much as I wish I could), but they keep, within reason.

by all means. take Donald's own advice, and go out and find a cheap 2X loupe with fungus all over the lens, to help everything look the same when it actually isn't, and never will be.

Drew, your exaggeration is part of what makes it hard to take you seriously. Sure, you're more experienced at this than I am, but nobody starts learning with perfection. They can't. Just as I'm sure you did, they start with equipment they can find and afford, make their early newbie mistakes on (I hope) cheap film, and build confidence and experience as they go.

 

[Donald Qualls]

Doesn't diffraction depend on the size of the print as well?

Just as with depth of field (and the "acceptable circle of confusion") magnification from the negative is a factor to consider. An 8x10 that will be contact printed can tolerate a good bit more defocus or diffraction than a 6x9 cm printed to 8x10, never mind a 35 mm negative at the same print size.

 

[grat]

I know of one example of someone shooting the same scene on 4x5 at f/32 and f/45, and doing a side-by-side comparison. There was noticeable softening at f/45, but in the particular case, it added enough depth-of-field that the tradeoff was worth it-- but barely. I can't imagine f/90 being usable for anything that isn't a pinhole.

 

[DREW WILEY]

"Circle of confusion". One more confusing term worth ignoring. But you are correct about contact prints. I gotta go into the darkroom in a few minutes to put a 6x9 neg in the carrier. It's those little ones that require the best technique, that is, if a nominal 16X20 print is going to be reasonably worthy of being in the same portfolio as prints the same size made from 4x5 and 8x10 negatives.

No way with 35mm, however. For 35mm I go alter-ego, and only make small prints, sacrificing detail for simple poetry, even using deliberately accentuated grain sometimes. But I will sometimes mix those 35mm prints with 8x10 contact prints in the same portfolio or presentation. The distinction between these is not only obvious, but dramatic. Yet the use of both salt and pepper is sometimes the best recipe.

 

[Sirius Glass]

If I was still shooting 8X10 chrome film, now at around $40 per shot with processing, I don't think I'd want to gamble on any of the shoot from the hip closeup advice about bellows extension on this thread. I'd want to know the factor exactly. And that's the case even with color neg and black and white film. If you have along one of those basic little aid devices, like the Calumet one I mentioned earlier, it's so darn easy that why forego it.

Per when the effects of diffraction significantly sets in, as a rough rule of thumb, it starts becoming apparent in enlargements from 4x5 film anything smaller than f/32. For 8x10 film, around f/64 is the limit, or maybe even f/45, assuming film in your holder is actually being held flat, which it often isn't. Sometimes sloppy adjustment in one factor disguises carelessness in another; but it's still there, and all adds up.
A mask can't cure something inherent to the exposure itself. It can simulate a little more edge definition, but that takes some experience if doing it darkroom style. But it can't add fine detail lost to begin with due to excessive diffraction

I completely disagree with Donald. A 4x5 film shot using a 210 lens at f/90 is going to look downright mushy with any degree of enlargement. At f/45, I'd be scratching my head too. Even an 8x10 enlargement at f/90 and the equivalent angle of view will look conspicuously soft. Only contact printers with zero magnification in the print can routinely get away with very small stops, undetected.

I used a spreadsheet that a past moderator posted to print out a bellows extension scale which I used rubber cement to attach to the rails of my 4"x5" camera. That way I can quickly check the scale to adjust for bellows length while I am in the field.

 

[DREW WILEY]

I one had a miniature 1/8 inch wide tape rule with proper marks for several of my lenses. But the Calumet gadget is easier.

 

[Alan Edward Klein]

I know of one example of someone shooting the same scene on 4x5 at f/32 and f/45, and doing a side-by-side comparison. There was noticeable softening at f/45, but in the particular case, it added enough depth-of-field that the tradeoff was worth it-- but barely. I can't imagine f/90 being usable for anything that isn't a pinhole.

As a landscape shooter, I've been told and follow the advice that it's more important to get the DOF. If you don't have that, you won't have to worry about diffraction.

 

[DREW WILEY]

With view cameras, you can often have you're cake and eat it too, if you wisely use the plane of focus controls (tilts and swings) inherent to view cameras, instead of resorting to merely stopping down. I've done numerous extreme close-up on 8x10 film stopping down only to f/32, for example. Some of those would look nose-up-to-the-glass sharp a even in a 40X60 inch print.

 

[DREW WILEY]

Donald, I'm not exaggerating at all. Sure, there are lots of chuck holes along the road, and a lot of unexpected turns in the learning curve. But that's no reason to lower expectations. Careless habits and compromises starting out just become entrenched bad habits afterwards. But I'd agree with starting out with a middle of the road film like FP4, which is a superb product regardless, and fully capable of excellent results.

 

[John Patrick Garriga]

@John Patrick Garriga While I'd say Drew is technically correct in what he writes, it's worth noting that he has a long history here of advising that any other than wavelength-level precision and perfection is unacceptable. I'd rephrase what he said above about sloppiness to mean that unless every single part of your equipment and process is perfect (and it isn't), you won't be able to tell diffraction from defocus at f/45 on a 150 mm lens (with 4x5 negatives, anyway).

If you follow Drew's advice, you might well give up before you actually expose and process any film.

Find out for yourself -- shoot the same scene at f/22, f/32, f/45, and f/64 (if your lens will stop down that far -- many won't even in large format focal lengths). Examine the resulting negatives with a loupe. Learn the difference between defocus and diffraction (hint: one is local and depending on distance to subject, the other is not). Then make your own decisions.

And of course, don't do your early learning at $40 a sheet for 8x10 chromes...

Trust me, I get it. I go from cameras to guns to radio to backpacking as far as my interests are concerned. I’ve noticed a general trend in each which is that everything is a science until you get good enough at it and then everything can be done on the sly. With backpacking, especially. I’m more of a day hiker myself (looking at going on longer trips) but every little piece of advice has to be met with technically true but usually not very useful talks about what difference an eighth of an ounce makes in your hiking bag. My current plan is, once I get all my gear in and some film, start off with paper negatives, then move on to some higher end film. I’ll probably stick with portra 160 for landscapes and 400 for portraiture.

Wish there was some way you could get a digital back that mimicked film to practice on, something low res but just so I could make sure all of my exposures were correct

 

[xkaes]

As a landscape shooter, I've been told and follow the advice that it's more important to get the DOF. If you don't have that, you won't have to worry about diffraction.

It's often a trade off -- or one good reason to take more than one shot of the subject at different lens settings.

 

[John Patrick Garriga]

Also, having trouble figuring out exactly what these knobs do. Bottom moves when I adjust my focus, is that supposed to help me find my focus again quickly when I lose it? Set it to 0 when I’m in focus and come back to it when I need to?
Top doesn’t seem to do anything. Can loosen it but nothing moves

 

[DREW WILEY]

That rotating device is related to the asymmetric tilt capability of your Sinar, and perhaps a couple other things. I learned how to use it long ago, then forgot all about it. It can be convenient when working with a predictable plane of focus in the studio, like tabletop setups. But I've ignored it for decades in actual outdoor use, where consistent planes are rare, at least in the mountainous West. Sinar had excellent handbooks on technique relative to their own cameras, but that's nearly all studio related. The F's and P's had different types of asymmetric calculation. I now mostly work with the prior Norma system, which doesn't have any such feature; but I don't miss that at all.

 

[John Patrick Garriga]

That rotating device is related to the asymmetric tilt capability of your Sinar, and perhaps a couple other things. I learned how to use it long ago, then forgot all about it. It can be convenient when working with a predictable plane of focus in the studio, like tabletop setups. But I've ignored it for decades in actual outdoor use, where consistent planes are rare, at least in the mountainous West. Sinar had excellent handbooks on technique relative to their own cameras, but that's nearly all studio related. The F's and P's had different types of asymmetric calculation. I now mostly work with the prior Norma system, which doesn't have any such feature; but I don't miss that at all.

I assume you're talking about the bottom knob, the one with the numbers?