What is PMK?

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I understand that it stands for Pyro-Metol-Kodalk. I understand that it supposedly gives most excellent results. What I don't understand is exactly what the process does.

From what I've read, it seems to be a develop-bleach-stain development method. Is that correct? Why (for example) would you choose to use this over a standard development method?

Furthermore, which chemical does the development, the bleaching, and the staining?

-- Hal Haygood (hhaygood@earthlink.net), March 05, 1999


Hi Hal. PMK is a staining developer (not bleaching) containing 2 developing agents, methol and pyrogalol. The staining is produced by the pyrogalol (or pyro on photo slang). Pyro was one of the first known developing agents, but just 10 years ago or so with the development of the PMK formula by Gordon Hutchings it was posssible to achieve high quality results by using pyro. To my opinion, PMK is absolutely unique developer which produces outstanding negatives. Negatives developed in PMK are very easy to print. The reason for this is that PMK gives very good highlight separation. The sharpness and grain are also good (sharpness is in fact very high with edge effects that only FX-1 can beat) with a drawback of speed loss with some emulsions. However, if you can leave without push processing and pay attention to some small details during development, try PMK and you will discover that your prints just look different. Evgeni.

-- Evgeni Poptoshev (evgeni.poptoshev@surfchem.kth.se), March 05, 1999.

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