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  1. #1

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    A question about Pyrocat, stain and washing : what are approx. your b+f levels ? Reading the blue channel on my densitometer with 13x18 FP4+ processed in an Expert drum Jobo and a CPA2, lowest rotation speed, I read 0.10 for a N development, and about 0.15 for a N+1. These are my first trials with Jobo, FP4 and Pyrocat, in trays b+f was of course lower, 0.08 with 13x18 and 0.06 with 4x5" for N time. But I suspect that a great part of this b+f in Jobo comes from the washing time, and that it is possible to reduce this level with a shorter process. What washing process, what time would you suggest for an efficient wash when using a Jobo processor with Pyrocat ?

  2. #2

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    [quote="Jimmy Peguet"]A question about Pyrocat, stain and washing : what are approx. your b+f levels ?


    Jimmy,

    Although I don't use Jobo I develop all of my sheet film with rotary processing, sheet film up to 5X7 in BTZS types tubes, and ULF film 7X17 and larger in Beseler and Unicolor print drums on a Unicolor motor base, ate about 15 RPM. I think the same issues of stain apply with my development methods as with Jobo.

    My b+f figures are not that different from yours. With FP4+ I get a b+f of about 0.08 at N development times and about 0.12 at N+2 development times. This is with the blue channel of the densitometer. Your figures are really quite similar to mine and I don't really believe you need to make much of an adjustment, certainly not by cutting back on washing time which may compromise the archival quality of your negative. You might add a pinch or two of sulfite to the working solution just before development and this should cut fog by about 0.02 to 0.05 depending on development times.

  3. #3

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    Sandy,

    I recently had surprises washing ABC negs with gentle agitation, resulting in low stain, I thought it could be same thing, washing directly in Jobo being much more violent (I washed during 30' as usual in trays, maybe a bit long for a Jobo ?). I developed a new set of 13x18 (or 5x7" for you), washing them quietly during 30' with several waters in trays, and I got exactly the same b+f values than those washed in the Jobo. I'm not used with pyro in rotation, stain seems to work differently : with ABC developed in trays, stain comes during washing, while Pyrocat negs are already stained after the fixer.

  4. #4

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    [quote="Jimmy Peguet"]Sandy,

    I recently had surprises washing ABC negs with gentle agitation, resulting in low stain, I thought it could be same thing, washing directly in Jobo being much more violent (I washed during 30' as usual in trays, maybe a bit long for a Jobo ?).


    I never wash the negatives in the drum. After the rinse in hypo-clear, or in my case a 1% sodium sulfite solution, I place the negatives in a tray for wahsing for 20-30 minutes. As far a I can tell there is no increase in stain during washing, and if so, it is very minimal.

    Sandy



 

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