Re: Dark reaction
In copper plate photgravure, they often senstize the gelatin tissue with dichromate then store it in a refrigerator until they use it. I am not sure how long it keeps.
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On Oct 29, 2009, at 2:44 PM, etienne garbaux <firstname.lastname@example.org > wrote:
Katharine wrote:Good point about Kosar. I have found his book immensely helpful in getting the most out of the carbon process, but other colloids do not act the same as gelatin.As noted, Kosar is fairly good on the dark reaction, except that the literature Kosar reviews and summarizes is almost entirely related to dichromated gelatin, which isn't precisely equivalent to dichromated gum. Studies on dichromated PVA give a closer approximation to the mechanisms of dichromated gum arabic, and very occasionally, one can even find direct studies of dichromated gum, as the one cited above.