Mix partial batch of HCA?

Discussion in 'B&W: Film, Paper, Chemistry' started by polyglot, Jul 26, 2012.

  1. polyglot

    polyglot Member

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    I realize that mixing partial batches of developer is risky because you can get very uneven dividing of minority ingredients. Does this issue apply to hypo-clearing agent? Reason I ask is that I don't think I have a 20L container handy (5gal pack), but 2 of 10L are readily available. Or should I mix it up at 2x concentration and then dilute more when using it? Will all the powder dissolve at 2x?
     
  2. anikin

    anikin Subscriber

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    If it's the Kodak's HCA packet you are talking about, I believe you mix it to make 1 gal concentrate and only dilute 1:4 when it's time to use it.
    The HCA does have several ingredients in it too. So theoretically it's not a good idea either. In practice I don't think you are going to hurt anything if you split the powder ;-). You might get slight variance in ph because of uneven metabisulfite, but most of us use a pinch and spoon method to mix HCA anyway, so being off 50% or so is really no big deal.