Pyrocat developing times

Discussion in 'B&W: Film, Paper, Chemistry' started by lallan, Apr 14, 2004.

  1. lallan

    lallan Member

    Oct 3, 2003
    Finished reading Sandy King's Pyrocat article on The development time charts at the end of the article are for BTZS tubes. Are these times equivalent to tray developing? Specifically, HP5 developed for UV printing. Thanks.
  2. KenM

    KenM Member

    Apr 22, 2003
    Calgary, Alb
    4x5 Format
    No, the times for tube processing will not work for tray processing. When developing in tubes, the film is under constant agitation (unless you use stand development - never used that, can't really comment on it) as opposed to mild agitation with tray development.

    You would therefore have to increase the tray development time to obtain the same contrast. I would suggest 20% as a starting point. My times for developing HP5 in P-HD EI 320 20C was something like 13 minutes - try for 15 minutes in trays, and adjust accordingly.