From: Christina Z. Anderson (zphoto@montana.net)
Date: 07/26/03-07:18:59 AM Z
<Clay said>forgetting to put dichromate in your
> mix before laying down a coat (Although, as I related to Stuart, I
> actually saved this by just coating the proper amount of saturated
> ammonium dichromate onto the dried gum and then letting that dry. A
> 'Hail Mary Pass' to be sure, but it did work)
> So, I guess I'll be comic relief.
> Clay
>
Actually, Clay, I think you were just receiving a psychic message from
the grave: Caspar Miller promoted this method around 1900. The benefit was
you could coat a bunch of paper with pigment/gum and store it for long
periods of time. Then, at time of use, you floated this on a 5% bath of
potassium dichromate to sensitize. OR brushed it on the BACK of the paper,
as some did.
Most people at the turn of that century were doing the presensitizing
of the paper with dichromate and storing that for long periods of time, and
then coating upon time of use with a mix of gum/pigment. I've done that and
it works very nicely!
Chris
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