Developing times for Pyrocat HD

Discussion in 'B&W: Film, Paper, Chemistry' started by Adrian Twiss, Jan 21, 2004.

  1. Adrian Twiss

    Adrian Twiss Member

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    I have just re-read the excellent article by Sandy King on Pyro developers in www.unblinkingeye.com. I have just one question about the developing time graphs for silver gelatin prints. Sandy stated that the test films for producing these charts were rotary processed using BTZS tubes. Whilst I have no idea how these tubes work I understand that rotary processing usually means shorter development times. As I intend to develop both roll and sheet films in daylight tanks do I have to increase the indicated times to take account of this method?

    Thank you

    Adrian
     
  2. Black Dog

    Black Dog Member

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    Times for continuous agitation are normally 15-20% shorter than times for intermittent agitation. So adding this figure should put you in the ball park.
     
  3. Jim Chinn

    Jim Chinn Member

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    I have found with HP5 and FP4 that normal times give me an excellent negative in my JOBO cpe2. TMAX/Delta 100 seem to need the slightly less time of about 10% to give me the best negatives. YMMV.