Dry Plate Speed & Shelflife

From: Robert Newcomb ^lt;newcombr@uga.edu>
Date: 03/01/05-10:53:28 AM Z
Message-id: <1f436420de51ad4c3256ef9efcfc4748@uga.edu>

I've been interested in making my own glass dry-plates to shoot in
camera - I like some of the "errors" introduced from hand poured
emulsions.
A couple of questions for all you knowledgeable people out there.
1) I have read that the speed of early dry-plates was about 7 stops
slower then the wet -plate process in use at the time. While I'm
certainly not trying to shoot action sports shots, we're talking Very
slow here. I have heard that the bottled silver emulsions have an in
camera speed of about ISO 1/2- maybe 1.
  Is their a component (bromide?) or procedure that will make a hand
poured dry plate at least as fast as wet plates?
2) I have also understood that early dry plates (hand poured) had a
useful shelf-life of only a few days or a week after being made in
which one must expose them. Is their a means of extending this
shelf-life to a couple of weeks or at least something more the a few
days? I'd hate to make them and then not be able to go out shooting
the next day so the plate spoil.
I understand that commercially prepared plates later overcame these
factors but what is possible of the home brewer?

Thank you,
Robert Newcomb
Received on Tue Mar 1 10:53:38 2005

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