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  1. #11
    Kerik's Avatar
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    Quote Originally Posted by Jorge
    I use .5 gr OA, 5 gr FO 27 ml of water.
    Hmmm... this is a pretty low FO concentration ~19%. I use ~27% solution - 6.75 gm FO, 1.2 gm OA and 0.5 gm EDTA (tetra) to make 25 ml. But, whatever works!

    Kerik

  2. #12

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    Quote Originally Posted by Kerik
    Hmmm... this is a pretty low FO concentration ~19%. I use ~27% solution - 6.75 gm FO, 1.2 gm OA and 0.5 gm EDTA (tetra) to make 25 ml. But, whatever works!

    Kerik
    Uh, you are right, I just went and checked. It is 7.5 gr of FO...

  3. #13

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    Kerik,

    This is what I was wondering about Michael's answer above : what is EDTA used for in sensitizer ?

  4. #14

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    Jimmy,

    I generally use:

    FO 15g
    OA 2g
    EDTA 0.75g
    H2O 55ml

    If I have any trouble getting the FO into solution, I'll add a pinch or so more EDTA to the mix.

    Note that the formula for FO is somewhat up to intrepretation, and you will find that the FO from one supplier will produce different results than the FO from another supplier. I believe theis is about the only compound that we use that is like this, with all the rest being more or less the chemical compound with a certain purity, and subject to little deviation.


    ---Michael
    www.mutmansky.com
    B&W photography in Silver, Palladium, and gum bichromate.

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