Exposure question

[coops]

I was watching a video of Fred Picker taking photographs. He metered the scene and there was a 3 stop difference between high and low values, (zone 8 and 5 in this case) He was anticipating shooting it at 60th sec at F/22 which happened to be correct. Because of the low contrast range, he decided to shoot between F/32 and F/45 for 60th and give the negative N+ 1.5 development.
Why not shoot it at F/22 and give it N+ 1.5?
I am sure the answer is simple but I cannot figure it out.

[Jim Michael]

Perhaps he figured his shutter speeds may not have been as well calibrated as his aperture.

[Gem Singer]

In simple terms:

Added development time to increase contrast also increases overall density.

Decrease exposure by closing down a stop, or so, then when development time is increased, the contrast will increase and the overall density will still be in a printable range.

[BetterSense]

Why not shoot it at F/22 and give it N+ 1.5?

If you had an ideal film, and you don't mind a bit more density, you could do just that, and that's what I would typically do. However, if you want the midtones to fall on a particular favored part of the curve, you can increase contrast by BOTH reducing exposure slightly and developing slightly more. This will move the shadows down and the highlights up, leaving midtone density more similar to the N situation. I prefer just to increase development and print through the added density. I shoot TMAX, and I don't see any tonal changes over differing exposures.

When I shoot 35mm TRI-X, I shoot it at 200 normally. If it's gloomy/rainy out, I shoot it at 400. It brings the density down a bit; density that is not needed for such a short subject/brightness range.

[Ken Lee]

The old maxim with film is: Expose for the shadows, and develop for the highlights.

The low values are critical: if you under-expose, they cannot be retrieved with longer development. Furthermore, development affects the high values much more than the low values.

The scene was of low contrast, and needed deeper shadows, so he placed them low. Usually, shadows feel dark, and he wanted them to look that way.

By stopping down a few stops, he placed the shadows 1.5 zones lower, namely Zone 3.5

By developing longer, he pulled the high values up by 1.5 stops, back to their normal level, around Zone 8.

Without extra development, the photo would have merely been underexposed by 1.5 stops. With it, the contrast range was expanded.

[coops]

All makes sense now. Thanks very much

[ki6mf]

The explanations above are all excellent. Keep in mind all meters are rated for Zone 5 - 18% Grey. So to get to zone 4 meter and change 1 stop. To get to zone 3 go 2 stops! This controls how light or dark your shadows will be, withing tolerances of film and gear. Then you control highlights by development.

[speedfreak]

If placing the shadows on zone 3 or 4 I wouldn't say he is underexposing, just placing the shadows further down the films curve. By placing the values lower to begin with and expanding development you will get less visible grain.

[Brian Ellis]

If placing the shadows on zone 3 or 4 I wouldn't say he is underexposing, just placing the shadows further down the films curve. By placing the values lower to begin with and expanding development you will get less visible grain.

I was under the impression that in general increasing development time tended to increase, not decrease, grain size.

[neil poulsen]

Here's my logic from what you've included in your post.

I'm thinking that the Zone "5" and "8" were what he read on his meter. This makes sense, because he would tape a zone system scale onto his Zone VI adjusted meters, and "5" corresponds to what his meters would place any value that was read.

The point in the scene from which he read his Zone 5 was intended to be Zone 3.5 in the photo. I conclude this, because he lowered the exposure by 1.5 stops to make that area 1.5 stops darker in the photo. (From f22 to half way between f32 and f45.)

I'm thinking that the point in the scene which he read as a Zone 8 on his meter was actually intended to be Zone 8 in the photo. I conclude this, because he expanded development by 1.5 stops, so that there would be a 4.5 stop difference between his low and his high. (3 stops plus 1.5 stops.) If the low was intended to be Zone 3.5 in the photo, this value plus the 4.5 stop difference gives Zone 8 for the high value in the photo.

This logic is consistent. I would probably want to see the video to be comfortable that this was also Picker's reasoning.

[neil poulsen]

I wrote my post without fully reading Ken's post. Looks like we agree. :D

[speedfreak]

Yes, increasing development may induce more visible grain. That's why when faced with a low contrast scene, you would place your important values as far down the scale as you can without losing it, then extend development and appropriate amount and if needed, you can always print up your values if development didn't take care of it.

[sun of sand]

he wanted darker darks with the same highlights
not literal values
which would create qutie a flat print

"low placemet"

[Brian Ellis]

Yes, increasing development may induce more visible grain. That's why when faced with a low contrast scene, you would place your important values as far down the scale as you can without losing it, then extend development and appropriate amount and if needed, you can always print up your values if development didn't take care of it.

I understand that. What I didn't understand was your statement that "y placing the values lower to begin with and [B]expanding development you will get less grain."

[ic-racer]

I was watching a video of Fred Picker taking photographs. He metered the scene and there was a 3 stop difference between high and low values, (zone 8 and 5 in this case) He was anticipating shooting it at 60th sec at F/22 which happened to be correct. Because of the low contrast range, he decided to shoot between F/32 and F/45 for 60th and give the negative N+ 1.5 development.
Why not shoot it at F/22 and give it N+ 1.5?
I am sure the answer is simple but I cannot figure it out.

I suspect this is B&W negative film. If that is the case, a low range of values in a scene means that exposure lattitude is large. You can do what you want with exposure and think you are doing some exact process :p .

[Bruce Watson]

I understand that. What I didn't understand was your statement that "y placing the values lower to begin with and [B]expanding development you will get less grain."

Because graininess is related to density, not necessarily development time. If you end up with less density, you end up with smaller grain clumps, in general. If you end up with more density, you should end up with larger grain clumps, in general.

Unless you are using color materials. Restrainers limit the size of dye clouds. In modern color negative materials, increasing density can actually result in *less* graininess. Crazy, I know. But that's what Photo Engineer (APUG) tells me (and I've seen the graphs). I have no reason to doubt him.

[speedfreak]

What Bruce said.

[Gem Singer]

I believe that Fred Picker was trying to point out: "with a flatly lit scene, when increasing the development time in order to increase contrast, you need to decrease the exposure time".

Increasing development without decreasing exposure will produce negatives that have increased contrast and increased overall density. They will be difficult to print.

He explained this principle in subsequent writings,