Monday, February 22, 2010

This is the key reference on DTR

I am still engrossed in

Photographic Silver Halide Diffusion Processes
Authors: Andre Rott, Dipl Ing, Edith Weyde, and Dr Ing.
Focal Press, London 1972

Which among other things describes the history and development, dozens of configurations, and many examples of diffusion transfer reversal techniques.  This claims to be part one of a two-part series published by Focal Press and promises a follow-on named "Instantaneous Photography" by Land.  But I cannot find a trace of the second book that is named here. Perhaps it never was written.

Not that it matters all that much right now, because Edith Weyde and Rott et al have done such a thorough job of describing the DTR process from a chemical and electrochemical aspect, that I have a hard time believing that we cannot extract enough information from it to at least get started producing DTR-assisted negatives, as I term them.

There is a section that talks about the use of lead acetate and other metal acetates in the receiver sheet of Polaroid materials which are not mentioned in any of the MSDS that we have on hand for 55.  But at least we know how to imbibe paper with lead acetate easily, and probably produce a number of different nucleating particles in a receiver layer with enough experimentation. Still, I wish I could find someone, anyone, with specific knowledge in that area. I have made inquiries, but no luck so far.

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