Here is the address for the flickr.com page containing my photos of Ctein: http://www.flickr.com/photos/106822406@N08/

I hope it works.

What I recollect from my visit to Ctein was that I asked him how long he left the matrix in contact with the print paper and he said it didn't matter. I have a specific memory that the dye will reach a saturation point and that is the maximum amount of color which will transfer. Since I was familiar with the theory of the Technicolor imbibition process it amazed me that time was not a critical factor. Ctein washed his print paper with a clear fluid containing acetic acid--that provided the proper ph. Otherwise there was considerable latitude in the amount of time allowed for the transfer. That might be a characteristic of Kodak DT. I found the Condax patent 2,952,566 very informative.