Divided D76 precipitate

Discussion in 'Darkroom Developing and Printing' started by Lew, Feb 18, 2004.

  1. Lew

    Lew Guest

    I've just had my Formulary dD76 mixed for a week. Sol A has a dirty,
    brownish, snowflake sized precipitate in it. Has anyone else seen this? Is
    it normal or what?
    Lew, Feb 18, 2004
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  2. Did you use tap water?

    Martin Jangowski, Feb 18, 2004
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  3. Lew

    Lew Guest

    Yes, but here in Brooklyn, NY the tap water is exceptional & I've never had
    any problems over the years with a wide variety of chemistries.
    Lew, Feb 18, 2004
  4. Lew

    Dan Quinn Guest

    Speaking of ALL photographic solutions, I can not think of ONE
    instance in which particulate matter is a contributing ingredient in
    the working solution.
    With repeated use some solutions do generate a little sludge. Divided
    D76 should have no precipitate, A or B.
    Just a thought; how much film got "mixed" into part A? Dan
    Dan Quinn, Feb 19, 2004
  5. Lew

    Lew Guest

    You're right, I really don't know whether it's precipitate or not. The
    solution was clear while unused. After 2 rolls of film the gunk appeared. I
    filtered a quantity to use today and the results look fine. Still like to
    know what's happening, though.
    Lew, Feb 20, 2004
  6. As Martin suggested, this is what normally happens when using the
    published formula of D76 or the alike made up with tap-water. First
    they are clear, after developing a roll or two you get some
    precipitate in the solution.

    I'm using Barry-Thorntons Two-bath (a metol/borate formula) this way
    with no ill-effects so far but this may depend on the rest of the
    processing conditions. Therefore, I would recommend to use distilled
    water to make stock as well as working solutions that do not contain
    any sequestering agents.
    Stefan Kahlert, Feb 20, 2004
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