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Any PMK Photo Formulary kit users here?

Rich Ullsmith

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Just looking for a sanity check here before calling the Formulary . . .plus, I am more comfortable asking stupid questions online than on the phone.

My understanding of the kit is part B is kodalk, and it is the crystal precipitate that requires shaking prior to use. My question is: is it necessary for all the precipitate to be dissolved prior to use? Because I can never get all the crystals back into solution, regardless of shaking and hot water baths. This is maybe the fourth kit I have used, and all have had undissolved crystals in the part B, so I have been working under the assumption that this is normal.

Any insights on this?
 

chriscrawfordphoto

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I had that same question, and I called Photographers Formulary to ask. They said it was not necessary for it all yo dissolve, and that it would not all dissolve anyway. Its been working just fine for me.
 
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Rich Ullsmith

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Thanks Chris. I had assumed as much, but there's that saying about making assumptions . . .
 
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Rich,

Solution B is a saturated sodium metaborate (Kodalk) solution. It really needs to be mixed with distilled water to get as much of the metaborate dissolved as possible. If you mixed with tap water, etc., you will likely end up with a lot of precipitate and a slightly weaker solution. This may only make a marginal difference in you results, but can result in negatives that are underdeveloped.

If you used distilled water to mix solution B, then the few undissolved crystals are a good indicator that you have the solution as saturated as possible (á la Rodinal). Shaking the solution puts a little of the undissolved chemical into suspension so it can be mixed into the working strength developer, where it quickly dissolves.

If you have large amounts of precipitate from mixing with other than distilled water, you can double the volume (using distilled this time) and then use twice as much solution B in order to get the correct amount of metaborate in your working solution (subtract the extra water from the water you add to mix a working solution for precise results).

Best,

Doremus
 

Axle

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Yep, I noticed the same thing. Again I keep using it and haven't had any issues!