Preliminary Pyrocat Experiences

Discussion in 'B&W: Film, Paper, Chemistry' started by Adrian Twiss, Mar 4, 2009.

  1. Adrian Twiss

    Adrian Twiss Member

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    As a Prescysol user I have grown to enjoy the benefits of Pyrocatechin developers. No disrespect to Peter Hogan (the man has to make a living) I thought I could save money by mixing my own pyrocat. I just developed 4 5x4 sheet films (HP5 plus) in trays and must say I am very impressed. At 24 degrees I find that 81/2 minutes gives me just over N contrast and 61/2 minutes is almost right for N contrast. This is with constant agitation and the film rated at 320 iso. I intend to try mimimal agitation in trays (one sheet at a time) for 9min 45 seconds with constant agitation for the first minute then 10 seconds every 3 minutes thereafter. I still fee I must refine my development times but my initial impressions are that this is a developer I can stick with.
     
  2. Tom Stanworth

    Tom Stanworth Member

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    its great. The only reason I dont use it now is that in Afghanistan the water quality is all over the place. I found that I lose speed compared to D76 (about 1/3 stop) and 1/2 the EI of DDX/Xtol, but get great tonality, acutance and most of all, amazing shadow separation. When I return to civilisation, the pyrocat will come out again, when i dont need the speed. When I do, Xtol with some rodinal thrown in is looking good, esp with foma 100 & 200 and Neopan 400.
     
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    Adrian Twiss

    Adrian Twiss Member

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    I printed some of the negatives yesterday and on balance I think my development times are too short. As a baseline I used the graphs supplied by Sandy King and developed for a contrast index of 5. One of my prints is a little flat needing between grade 3 1/2 and 3 3/4. The negative I developed for 8 1/2 minutes is more like N rather than N+ on reflection. Some more experimentation needed I think.