Pyrocat - mixed films in same tank

[Thomas Bertilsson]

Anybody with more chemical experience and knowledge than I - do you know if it's not preferable to mix films in the same developing tank when using Pyrocat?
I recently had a thread started with some problems with Plus-X in 120. Two rolls of Tri-X and one of Plus-X together. Tri-X came out fine. Plus-X had all kinds of marks on them. Irregular too.
Then I processed some Plus-X in Xtol 1+3 and they came out just fine. Not mixed with Tri-X, though.
Anybody ever had that happen?
I use Pyrocat-MC at 1+1+100 @ 70*F. 13 minutes, agitation full first min, then every three minutes. I presoak for about 3 minutes, water stop, and Hypam 1+4 fix. Then I use a roll film washer to get the fixer out of the emulsion.

Thanks,
- Thomas

 

[Paul Cocklin]

I've done T-Max 100 and FP4+ in 120 at the same time before. No problems with them, but I don't know if it's advisable or not. Mine was Pyrocat-HD 2:2:100 at 8 minutes @ 68*F, full 1st min agitation and 10 sec a minute thereafter, with a 2 minute presoak and water stop, TF4 fix.

 

[Gim]

Hi Thomas
I have mixed different brands of 35mm, 35mm and 120, in the same tank with pyrocat and other developers, presoak or not, over the years and have never had a problem that had anything to do with the developer. I don't believe the developer cares what the film is.

Have enjoyed seeing what you have done at the gathering.
Best, Jim

 

[craigclu]

Thomas, did you yet try the Plus-X in PyroCat by itself? This should answer your question.... There are some film combinations that I've heard can lead to strange results but I haven't heard of valid explanations. As an example, Ryuji has described some strange results in some of his developers in regard to this when mixing film types in the same tank. I imagine there could be some dissimilar pH behavior based upon emulsion differences, perhaps at important points in the development. The PyroCat may have additional issues because of the tanning timing/behaviors? My elementary chemistry knowledge would certainly defer to those more learned and to their opinions!

 

[Ian Grant]

Over the years I've regularly processed various films together in a variety of developers. It really makes no difference.

Ian