Rapid Film Development

Discussion in 'B&W: Film, Paper, Chemistry' started by Dr.Kollig, Jan 8, 2005.

  1. Dr.Kollig

    Dr.Kollig Member

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    I found the time to mix some of Jdefs rapid developer, with two minor changes I used K-Carbonate instead of Na-Carbonate, which I do not stock and the Benzotriazol was added as powder, not as solution.

    During lunch break I shoot some pictures with a M5 on Tura 100 ASA film, Emulsionnr. 667 (it is Agfa, we sometimes have the same emulsionnumber from Agfa and Tura). 90 secs at 20°C, Jobo CPE2 with lift. Negatives were enlarged 15 times, as usually for testing.

    To cut the story short, resolution looks very good, based on the bricks of the old building, grain is very fine. As the metering of a Leica M5 is ...well ...flexible, I can not comment on film speed.
    If I compare this with results from developers based on Catechol grain seems smaller and resolution might be higher.

    Also found some of my 2-Minute developer, with this the resolution seems lower with similar grain size.

    Rapid development is not that uncommon many labs use elevated temperatures, strong chemistry and times around 80-100 secs.

    Wolfram
     
  2. Dr.Kollig

    Dr.Kollig Member

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    Jay, simply cut your water to 50%! Using 36 g Na-sulfite per litre, you could cut down the water to 500 ml, the theoretical limit of solubility is close to 200g/l, the practical limit around 100g/l. It might he necessary to exchange Na-carbonat for K-carbonat.

    Wolfram