When a working PJ I carried a quart size kit along with a 1 quart size bag of Kodak fix, a small bottle of Photo Flow, a Stainless Steel Tank with 2 35mm reels. If I could not get my film out to the wire for processing I found that Diafine was easiest to work with in the field. Temperature range from the 50s to the 90s, 3 mints part A, 3 mints part B, no stop, running water rinse , then into the fix, wash and photo flow. Hang dry. Oh and a changing bag. As noted above I could process both Plus X and Tri X in the small tank, and there was a push. Problem was that I needed to figure out if I needed to process or could have the film sent to local office or back to London or find a local lab that would process. If I was going to process I needed to push the film. In the 70s the older emulsions were thicker and I could shoot Plus X at 400 and Tri X at 1200, Grain is very small, but contrast is low and I found the negatives to be mushy. I've read old post of folks pushing Tri X to 1600 by developing 2, same part A and b, but a very long rinse to remove all of part b , then back into A and b again. I never tired that, seems too risky, just a very amount of part B into A kills part A. Once mixed it lasts a very long time. I had to print on much harder paper contrast, I normally develop to print at grade 2, with Diafine, grade 4.
With D 76 you can develop stock, 1:1 or 1:2 for acuance with larger gain. D76 is a well balanced developer with the sweet spot of gain, contrast, and speed. Diafine, you get what you get, it was always my developer of last resort. BTW, T grain films do get a boost in ISO, at box speed or even lower. Reason is the emulsion is so thin that only a small amount of part A can be absorbed.
