I just read an article on doing testng for finding the proper proof time (minimum time for maximum black), finding personal exposure index, and normal developing time.
Proof time is straightforward. Regarding exposure time, if shooting say a 400 speed film, and the best of 6 negatives exposed at different speeds, the one that prints just slightly lighter than the papers maximum black is at a speed of 200, I assume I shoot that film at that speed from now on, as long as I am consistent with developing and printing techniques?
Regarding normal development time, I shoot six sheets of film of say a zone 7 range, and develop for 60%, 80% through to say 130% of the developer manufacturers time for a given developer, temp etc I am looking for a negative that prints slightly lighter than the white paper, and that is my ideal developing time.
So lets say for the paper I use, my minimum black is 20 secs, and the film speed I use is 200 and 8 mins is my developing time. In practice, if I meter zone 3, and then zone 7, develop my film at 8 mins, I should have a good negative (assuming I metered correctly) that should proof well at 20 seconds with my paper. And I can use the negatives I used for testing on other papers and record minimum time/max blacks etc?
Is this basically correct, or am I missing something?
I want to do this this weekend, so any help is appreciated.
Thanks