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Shen45
21-Apr-2007, 05:58
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

Mark Sampson
23-Apr-2007, 09:21
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.

Eric Woodbury
23-Apr-2007, 09:35
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.

Jim Noel
23-Apr-2007, 09:45
Storing the chemistry in a warm place should eliminate the crystal problem.

Eric Woodbury
23-Apr-2007, 11:23
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.

Shen45
23-Apr-2007, 18:05
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

steve simmons
24-Apr-2007, 09:51
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

Eric Woodbury
24-Apr-2007, 09:57
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.