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Gcastillo1986
6-Sep-2020, 05:13
I use FA 1027 to develop my 4x5 sheet film using the b’s reel and the 1000ml Paterson tank. Does anyone have experience using individual development times for sheets of film with the same mixed quantity of chemicals? Logic tells me if I can develop 6 sheets in one shot under normal circumstances, I should be able to develop 2 at base development, 2 at a push +1, and 2 at a pull -1 during the same development session with the same 1000ml of developer. I don’t want to use 3000ml of developer for these same 6 sheets. Any ideas or experience out there?


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Alan9940
6-Sep-2020, 06:34
I sure each has their way of working, but I don't ever re-use any developer. If I'm doing expansion/contraction, I'll batch those sheets together and develop in fresh chemistry. The only time I do normal/expansion/contraction during the same development cycle is when using my homemade tubes; each has fresh developer in each tube, only the time varies.

Doremus Scudder
6-Sep-2020, 11:44
The trouble is that once you've developed two sheets in your developer, you've both weakened it some and oxidized it some (plus added some bromide) so that the same developing time will not work for subsequent negatives. So, as long as you know this and test for how much longer you need to develop subsequent negatives, you should be fine.

If it were me, I'd start with the N+1 negatives first, developed at your standard N+1 time, then follow those with your N negatives, developed at your standard N time plus 10% or a bit more (for starters). Follow this with your N-1 negatives at your N-1 time plus about 15% and see how things turn out. After a run or two, you'll have refined the time adjustments and should get fairly consistent negatives.

If you find yourself needing to do this often, you may want to consider a couple other options.

Option 1: use more dilute developer for a longer time one-shot.
Option 2: consider a replenishment regime (I understand replenished Xtol is easy and lives very long).
Option 3: find a way to develop all negatives in the same batch, just introducing them into the developer at different start times. (FWIW, I do this all the time with trays. Let's say I have six negs, two each N+1, N and N-1. I'll start with the two N+1 negs, shuffle them for the appropriate amount of time, then add the N negatives, shuffle a bit more and finally, at the right time, add the N-1 negs. That way, they all go into the stop bath at the same time. You likely can't do this with your Paterson tank, but maybe you can rig up a tank with hangers or use trays for mixed batches?)

Best,

Doremus

Jim Noel
7-Sep-2020, 18:30
The relatively low cost of chemicals doesn't make them good candidates to use more than once.

Dugan
7-Sep-2020, 19:07
I agree with Jim N.
Reusing chemicals, particularly developer, is false economy, considering the cost of film and your time spent shooting...or re-shooting.