Favorite aperture?

[Corran]

I'm a landscape shooter...

f45 does it for me. My Rodenstock's are as good at 45 as they are at 22. I like depth of field. I'd like more if I could get it.

Lenny

Hi Lenny. Are you saying that you don't have any noticeable degradation due to diffraction between f/22 and f/45?

I'm just wondering. I am not saying I do see any...I don't shoot past f/32 on 4x5 usually, but usually always at f/22 or wider. I seem to notice a little more detail in scans at the wider apertures of f/16, f/11, etc., but that never translates to my darkroom prints.

[IanG]

Bryan, I think you'll find in previous threads many of us have found no preceptable degredation at f45 (with lenses deesigned fof 5x4 use). Many of my lenses have a marked f64 and a couple f90 but I acn't remember ever using them past f45.

You'll also find a breakdown somewhere of the apertures used by John Sexton and f45 is one he's used quite often.

Ian

[Doremus Scudder]

Degradation due to diffraction is a direct physical result of the size of the aperture. It has nothing to do with lens design.

Keep in mind, however, that even with rather stringent standards for the circle of confusion in the print, the effects of diffraction from a 4x5 negative (printed fairly full-frame) shot at f/45 will not be visible to the critical viewer until the prints are significantly larger than 16x20 inches. Even a 20x24 will not exhibit apparent degradation from diffraction unless the viewer is less than 18 inches or so from the print, much closer than "normal" viewing distance.

Upshot: we can safely use very small apertures on 4x5 and still print fairly large without significant image degradation from diffraction. An 11x14 inch print from a negative shot at f/64 still has a diffraction-limited CoC of about 0.066mm, which is below the resolution powers of the eye at normal viewing distances.

To answer the original question: I like f/32 on 4x5 a lot. It's my "go to" stop if I have any doubts about DoF issues and seems to be one I end up using most anyway. I measure focus spread and set aperture for optimum based on a CoC of 0.066mm. I don't have any qualms, however, about using f/64 if needed for DoF. I just make a note not to print that image too large.

Given that most lenses designed for 4x5 use have their optimum aperture at f/22, and that diffraction degradation is not objectionable (for me at least) till f/45 or greater, the aperture range to use is a no-brainer. The only exception is for those who want out-of-focus areas in their prints and must use larger apertures, or even shoot wide-open. Lens aberrations at larger apertures are much more of a concern than diffraction however...

Best,

Doremus

[cjbecker]

My favorite is around f11 for my 3/4 portraits. Thats what i set as the standard for my series that im doing. Have a new series im doing soon so will have to figure out which aperature will be the one for it. I like series to flow well and that includes the dof.

[IanG]

Degradation due to diffraction is a direct physical result of the size of the aperture. It has nothing to do with lens design.

Keep in mind, however, that even with rather stringent standards for the circle of confusion in the print, the effects of diffraction from a 4x5 negative (printed fairly full-frame) shot at f/45 will not be visible to the critical viewer until the prints are significantly larger than 16x20 inches. Even a 20x24 will not exhibit apparent degradation from diffraction unless the viewer is less than 18 inches or so from the print, much closer than "normal" viewing distance.

Upshot: we can safely use very small apertures on 4x5 and still print fairly large without significant image degradation from diffraction. An 11x14 inch print from a negative shot at f/64 still has a diffraction-limited CoC of about 0.066mm, which is below the resolution powers of the eye at normal viewing distances.

To answer the original question: I like f/32 on 4x5 a lot. It's my "go to" stop if I have any doubts about DoF issues and seems to be one I end up using most anyway. I measure focus spread and set aperture for optimum based on a CoC of 0.066mm. I don't have any qualms, however, about using f/64 if needed for DoF. I just make a note not to print that image too large.

Given that most lenses designed for 4x5 use have their optimum aperture at f/22, and that diffraction degradation is not objectionable (for me at least) till f/45 or greater, the aperture range to use is a no-brainer. The only exception is for those who want out-of-focus areas in their prints and must use larger apertures, or even shoot wide-open. Lens aberrations at larger apertures are much more of a concern than diffraction however...

Best,

Doremus

That's probably the best summary I've seen on these issues. In the end it's the results that count and knowing how to get the results you want from a camera/lens/film combination.

Ian

[Lenny Eiger]

Hi Lenny. Are you saying that you don't have any noticeable degradation due to diffraction between f/22 and f/45?

In a word, yes.

Especially since you have added the word "noticeable" in your question. I once suggested that diffraction didn't exist, and folks here read me the riot act, not unfairly I might add. I won't do that again.

However, there is a difference between the theoretical and actual results.

I have excellent lenses and an excellent scanner. I've tuned my film and developing to a very tight grain structure. The limits are not on the capture side anymore. (Uhhh.. as long as I focus the camera properly, of course, and don't kick the tripod while its exposing.) I believe the limits are now on how sharp the printer can print the image with its stochastic dot pattern...

Lenny

[Brian Ellis]

Brian, I can't think of a shot where depth of field isn't relevant - to me (I guess I am that weird, or old or something). However, even if it wasn't, it seems that what you're saying is that in that case, then maximum sharpness should be the default. Certainly you are entitled to this preference, however, I wouldn't be able to suggest this was a rule. Mine personal rule may be f45 all the time, unless I can't for some reason. But I don't think we can make rules for others. Maybe your weren't attempting to and that's fine... I'm just saying I don't think there is only one way to look at this...

Lenny

What did you see in my message that would make you think I was trying to establish a rule for others? The OP asked what our favorite aperture was. I responded. Nowhere did I say what anyone else should do and I certainly didn't say or imply that maximum sharpness should be the default or "the rule" when depth of field wasn't a consideration.

There are two situations I occasionally encounter in which depth of field isn't relevant to my choice of aperture. One is when photographing a flat or essentially flat subject such as a wall or the smooth face of a rock or a painting or anything else where there's little or no distance from near to far and I'm not real close to the subject. Another is when the nearest part of the scene or subject that I'm photographing is so far away that I know that given the lens I'm using everything from near to far is going to appear sharp no matter what aperture I use. Being weird or old or something has nothing to do with it.

I don't know exactly what your point is when you say you don't think there is only one way to look at this. I didn't suggest there was.

As an aside, I agree with your statement about diffraction, given in response to someone else's question. I've said here many times in response to questions about diffraction that I think large format photographers get too hung up on it. Diffraction just isn't a big deal with a 4x5 or larger negative and a print in the range of 16x20 or smaller.

[Leigh]

I once suggested that diffraction didn't exist...

That's close to being true.

In fact, diffraction is a function of the __absolute__ diameter of the aperture, not the relative (f/#) diameter.
So as the lens focal length increases, you can use smaller relative apertures without a noticeable problem.

Given that lens manufacturers are really fixated on quality, do you think they'd put f/64 or f/90 positions on
a shutter if the image was actually degraded at those settings to the point of not meeting their standards?

This is why so many classic images were made on large cameras with long lenses at very small aperture settings.

- Leigh

[Corran]

You know I always wondered about that. It made sense to me that it would depend on the relative size of the aperture.

Thanks for your opinions Lenny. Like I mention, I feel like I've not seen a problem so lately I've been shooting at f/32 occasionally. I won't worry about it anymore.

[Old-N-Feeble]

I don't really like the term "normal viewing distance". What is that, precisely? A 4x5 viewed at 10 inches? An 8x10 viewed at 20 inches... a 16x20 viewed at 40 inches? If so, then what's the point, barring presbyopia, of printing larger than 4x5? I want folks to be interested in a 120x240 inch print and be able to walk up to it and view fine detail. Okay... I can't carry a 12x20 camera these days but a 4x8 comes pretty close.