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Thread: PMK -- Crystals in part B

  1. #1

    Join Date
    Nov 1999
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    PMK -- Crystals in part B

    I noticed recently that crystals have developed in part B of my PMK and I was wondering if anyone has had similar happen to them.

    If so have you noticed any detrement to the contrast of your negs?

    Steve

  2. #2

    Join Date
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    now in Tucson, AZ
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    Re: PMK -- Crystals in part B

    PMK part B is just a nearly saturated solution of Kodalk, or "KOdak balanced ALKali". (sodium metaborate?). The "K" in PMK. Yours has saturated, thus the crystalization. I'd measure how much solution B you have, add an equal amount of distilled water, and mix. Then when preparing a working solution of developer, use twice as much of the (now-diluted) solution B. It's worked for me.

  3. #3
    Eric Woodbury
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    Dec 2003
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    Re: PMK -- Crystals in part B

    I did the same as Mark. I mix part B at half strength and use twice as much. Recently I started to see crystals again (cold winter), so now I measure and mix B every time.

  4. #4

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    Re: PMK -- Crystals in part B

    Storing the chemistry in a warm place should eliminate the crystal problem.

  5. #5
    Eric Woodbury
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    Re: PMK -- Crystals in part B

    Jim, I don't have a warm place. It snowed at my house on Friday morning. Maybe next week it will be warm. Spring comes early and stays a long time.

  6. #6

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    Nov 1999
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    Re: PMK -- Crystals in part B

    Quote Originally Posted by Jim Noel View Post
    Storing the chemistry in a warm place should eliminate the crystal problem.
    Hi Jim,
    considering that the temperature here has been averaging very high summer temperature for the last 6 months I doubt temperature is causing the problem.

    I think I will mix "B" at half strength and see if there is any difference.

    Has anyone noticed any change in negatives if "B" has started to develop crystals?

    I think I have but I'm not certain. It is very small if at all?

    Steve

  7. #7

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    Dec 1999
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    Re: PMK -- Crystals in part B

    If the temp gets too low it may crystalize a little. However, the solution is so saturated the negs should be ok anyway.

    This according to Gordon Hutchings

    You can also either warm up the solution or add water and then make a stronger mix - say add 50% more water to the B solution and then use 50% more of B in the mix.



    steve simmons

  8. #8
    Eric Woodbury
    Join Date
    Dec 2003
    Posts
    1,528

    Re: PMK -- Crystals in part B

    My EDTA solution does the same thing. It gets these beautiful little needle crystals suspended in the solution. I just shake that up and measure it out and say a little prayer.

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