Pyrocat Mixing Question

Discussion in 'B&W: Film, Paper, Chemistry' started by jbrodkey, Oct 31, 2003.

  1. jbrodkey

    jbrodkey Member

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    I mixed my first batch of Pyrocat using the kit provided by Photographer's Formulary. The results on HP5+ were good. I just shot some film and developed after a minimum of testing.The question is this: I was surprised that the chemicals came in individual little packets, some containing as little as a small fraction of a mg. Also, I'm not sure that I got all the carefully measured chemicals out of their packets without leaving a little on the sides. It seems to me that this problem might lead to inconsistent results. Do others using the kits see inconsistent results - or shouldn't I worry?
     
  2. Francesco

    Francesco Member

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    I got that kit too and the kit from Lotus View in Austria. I did not get any inconsistent results with the PF kit despite being unable to completely empty the individual packets of chemicals. The kit from Lotus View comes in liquid form and in very nice plactic containers. I like that convenience very much and peace of mind that all has been mixed properly.
     
  3. Donald Miller

    Donald Miller Member

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  4. Jorge Oliveira

    Jorge Oliveira Member

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    Yup. Phenidone in alcohol (the purer, the better) is a very good way to handle it; very good keeping properties.

    Jorge O
     
  5. L Gebhardt

    L Gebhardt Subscriber

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    I just mixed up my first batch from PF. The directions for part B say to add the 100g potassium carbonate to 75ml of water, then add water to make 100ml. Once I added the potassium carbonate I could not get it to desolve all the way, plus the total volume was over 100ml.

    I then found the recipe on http://unblinkingeye.com/Articles/PC-HD/pc-hd.html uses 100ml of water to 100g potassium carbonate. So I added 25ml of water and it all desolved.

    Which is right?
     
  6. sanking

    sanking Member

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    The correct formula is the one at unblinkingeye.eye. You add 100g of potassium carbonate to 100ml of water. Add the chemical very, very slowly with constant stirring. The total amount of solution after mixing will be around 125ml so in the end your mixing method gave about the same result and it should work well.
     
  7. Black Dog

    Black Dog Member

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    A good way to deal with chemicals in packets is to open the packets and then immerse them in the water you're using to mix the stock solution-that way there's no residue left in the packets, especially if you swill them round a bit.