RE: "dry plate" negatives

[ken watson <watsok@frii.com>]

There are technical process books ( maybe the one below is the one I have
seen ) that I have run across at a near by university library that explain
this in detail. So you may want to check there.  The whole thing is
interesting and I have thought about trying this myself. IF you can not find
any info close by email me and I will snail mail you the directions I have
found.

The early gelatin plates did not age well due to excess chemistry in the
gelatin. Once they figured out to wash the excess out  ( noodle - ing )they
were  pretty much modern emulsions. My directions caution that this washing
does dilute the emulsion and they have various ways of precipitating the
washed emulsion out of solution. I think most / all start out orthochromatic
and one then needs to add VERY EXPENSIVE dyes in very small amounts to make
it panchromatic, if you care to do so.  Also you can adjust the speed by
"aging" the emulsion longer or shorter. As we experience in commercial
products there is a grain size vs speed tradeoff.

..-----Original Message-----
..From: Baird, Darryl [mailto:dbaird@umflint.edu]
..Sent: Sunday, August 26, 2001 10:48 PM
..To: alt-photo-process-l@skyway.usask.ca
..Subject: RE: "dry plate" negatives
..
..
..Try _Silver Gelatin_ by Martin Reed and Sarah Jones, it should fulfill
..your needs nicely. Nice book.
..
..-Darryl
..
..
..-----Original Message-----
..From:	david distefano
..Sent:	Sun 8/26/2001 9:34 PM
..To:	alt-photo-process-l@skyway.usask.ca
..Cc:
..Subject:	"dry plate" negatives
..
..Could someone suggest a good website or book that would show how to
..make
..an emulsion to put on glass plates.
..
..
..
..