Re: Dark reaction
i concur. i think this is more or less common knowledge to the carbon
printing folks.
at least i came across that practice quite often when reading about
carbon printing.
i think they freeze it though, not just refrigerate.
phritz
Mark Nelson schrieb:
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.
Mark Nelson
www.PrecisionDigitalNegatives.com, PDNPrintForum@YahooGroups,
www.MarkINelsonPhoto.com, sent from my iPhonetypeDeviceThingy
On Oct 29, 2009, at 2:44 PM, etienne garbaux
<photographeur@nerdshack.com> wrote:
Katharine wrote:
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.
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.
Best regards,
etienne
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