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I was reading up on film development by PMK in The Film Developing Cookbook. On page 76, the authors state (as one of the reasons PMK is a good formula) that PMK contains no restrainer, which is good because "most restrainers, especially benzotriazole, tend to impair sharpness." Does anyone know whether benzotriazole would compromise the sharpness of printing paper as well? The reason I ask is that benzotriazole (I believe this was marketed in some form for a long time by EK as "BB" solution) is the key variable in a well thought-of amidol print developer solution known as "Fein's Formula".... What do you think? -jeff buckels (albuquerque)

-- Jeff Buckels (jeffbuck@swcp.com), August 30, 2001


I doubt it. I suspect Anchell and Troop are referring to a supression of edge effects when they refer to this, although I'm at a loss to understand the mechanism for the same. But even if we agree with them for a moment, the loss of edge effects only works because film is never developed to completion. Paper is typically developed to completion which renders such an argument moot for paper developers. If I have misunderstood and they are talking about a supression of resolution on paper, I would be very hard pressed to believe it because most papers resolve way, way more than the eye can resolve i.e., the limiting factor on resolution tends to be the lens/film/enlarger lens system and not the paper. However, on the whole, I agree that typically developers that need restraining have a very high level of alkali and therefore reducing the alkali is a better first line of attack than adding bromide or benzo. Cheers, DJ.

-- N Dhananjay (ndhanu@umich.edu), August 30, 2001.

"Will Benzotriazole impair the sharpness of prints?"

-- Pete Andrews (p.l.andrews@bham.ac.uk), August 31, 2001.

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