Speed loss with Pyrocat HD

Discussion in 'Black and White' started by arrthur_nichols, Aug 19, 2002.

  1. Hi,
    I recently mixed some Pyrocat HD and developed some HP5+ with it. The
    film speed was about ASA 160 which is half what I usually rate it at
    im PMK. Has anyone seen this or perhaps I made a mistake in mixing.
  2. I can't compare to PMK but EI 160 is exactly what I got for HP5+ in Pyrocat-HD. Other films showed a similar loss. I get EI 320-400 in D-76 1:1.
  3. Pyrocatechin formulas are not known for giving full speed. In most formulations pyrocatechin is used as a compensating developer, generally requiring increased exposure. I've always used an EI of 200 for HP-5+ with both PMK and Pyrocat-HD, but never really cared for the results.

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