pushing tri-x/tmax; how do you develop?

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Hi!

I'm still trying to understand this "pushing" process, both in terms of taking photos and in developing. Let's say I want to take photos of an inddor party with 400 film (without using flash), basically I'll have underexposed all my shots, right? (My nikon n65 has no manual ISO setting, so I'll set my camera on -1 EV for the entire roll).

Now, when I go to my darkroom to develop it, I want to develop at 800 (or I could do -2EV and develop at 1600, if I want, although I'll get more grain, right?). In looking at the Kodak Technical Publication F-32 for tmax films (a pdf available at the kodak web site), it seems that the developing times for one stop push are the same (at least using D-76, which is what I use). Isn't the developing time supposed to increase for push processing, or is this supposed to be confusing?

And I take it there aren't any additional changes in the protocol for stop bath, fixing, etc.?

Thanks for your help! Justin

-- Justin Indyk (indyk@pharm.sunysb.edu), August 12, 2001

Answers

If you set your camera for 800 film, then Tri-X should be about a stop underexposed. Experience shows that a little push of about 20 percent longer development time is good, and grain is not objectionable. Stopping and fixing remain the same. I've never pushed to 1600, but I suppose 30 percent might be called for, although contrast inherent in the scenes will be increased, along with grain. I believe pushing doesn't increase film speed but just makes highlights denser. So I prefer to use film at the speed it works best, and for me, Tri-X is best at 400.

-- Keith Nichols (knichols1@mindspring.com), August 12, 2001.

Kodak's processing data for T-MAX developer show the same development times for both the normal film speed and for a one-stop push (This is true for T-Max films; I can't recall if it applies to others). In other words, T-Max is a push developer that accomplishes at least a slight increase in the actual shadow density (Maybe 1/3 stop?).

Another thought would be to shoot TMax P3200 instead of tri-X; but shoot it at 800 or 1000. (Its true speed is really 800). By doing this, you won't have to give up any shadow speed at all.

-- Bob Fleischman (RFXMAIL@prodigy.net), August 12, 2001.


I should have said, you won't have to give up any shadow detail.

-- Bob Fleischman (RFXMAIL@prodigy.net), August 12, 2001.

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