OT: Need help with some old film

[Mods, move this if necessary]

I've been doing more and more analog photography, and earlier this week got 36 rolls of an unusual Kodak film. It's labeled as Kodak Traffic Flow Recording Film SO-370. There are two threads about this film online, one started by me on APUG, and one on photo.net.

The trouble with the film was 1) figuring out the ASA, and 2) how to develop it. I shot an ASA test, and then a developing time test (12:30 @ 74°F in HC-110 Dil H). I'm pretty happy with the developing time, so I'll be using that in the future.

What I can't decide on is which ASA to use. From 50 ASA to 125 ASA, the results look pretty good. Some darkening and grain at 100 & 125, but not enough to really call it bad. I was hoping I could get some opinions on what ASA you guys think looks the best.

I'm not looking for critique on the shots, as I know a few were out of focus. These were done on a Canon EOS 630, on a tripod, single constant daylight light on a stand camera right, Program mode, adjusting ASA from 6 up to the max of 4000, and letting the camera make the exposure adjustments based on the ASA change. Lens was an EF 50mm 1.8 MkI.

Just interested in what you feel is the most pleasing from the film aspect (grain, contrast, shadow detail, highlight retention, etc.).

Here is a link to the full test shot album with a contact sheet: http://s486.photobucke​t.com …Film/SO-370%20film%20test

If you select 'OTHER', please post which ASA it is that you prefer.

1) 50 ASA

This is virtually impossible to do on JPEGs, especially for slow films, where the grain is generally very small to begin with. However, I can give you some rules of thumb for B&W film:

1. Overexposing (i.e. decreasing film speed) will lead to increased grain. NOTE, this is *only* true of true silver halide B&W film; for C-41 B&W (and colour), grain decreases with overexposure. For all films, sharpness decreases with overexposure.

2. That said, you always want to err on the side of overexposure; exposure for negative film should always be keyed to the shadows. Negative film has enormous highlight latitude, but very little shadow latitude, so the old maxim holds true; "Expose for the shadows, develop for the highlights".

3. These all look pretty much the same to me. You've only tested the film over less than a 1.5 stop range; that's nothing. Try shooting it at 25, 50, 100, 200, 400, and 800. Tri-X (for e.g.) will work well at all of these speeds (with the above caveats re: sharpness and grain).

What's up with the finger in the 80 picture?

Dude, they are all good looking!
Just don't use digital mentality with film

Picture North Carolina wrote in post #17105194
What's up with the finger in the 80 picture?

I guess she really doesn't like that rating.

Can't really tell with that test. You could make a more analytical test with a step wedge or just shoot it at 64 which looks fine - the deep shadow behind the right arm seems to have decent detail. I think the contrast is a little high and would back off a tad with the development, but if you're happy with it then go for it.

J Michael wrote in post #17106176
Can't really tell with that test. You could make a more analytical test with a step wedge or just shoot it at 64 which looks fine - the deep shadow behind the right arm seems to have decent detail. I think the contrast is a little high and would back off a tad with the development, but if you're happy with it then go for it.

I'll just second this and save some time.

Best results of what? The ASA speed rating would affect the grain size and the shutter speed needed for handheld shots. ASA 100 is good all around for fast, and wide lenses. ASA 100 films can generate do fine at EI 200.

Answer is: depends on the make up/design of the film. There are poor ISO 100 speed films and great IS I 400 speed films. ISO isn't the main point of consideration.