cyanotype II on glass

Hi:

A friend of mine is trying to do cyanotype II on glass. He is putting
down a layer of gelatin with chrome alum as a hardener, letting this dry
and then coating it with cyanotype II.

He says the cyanotpe goes on beautifully, but once it dries it crystalizes
and is insensitive to exposure.

We think its likely the chrome alum reacting with the cyanotype II - any
other ideas what would cause this?

Gord
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Gordon J. Holtslander Dept. of Biology
holtsg@duke.usask.ca 112 Science Place
http://duke.usask.ca/~holtsg University of Saskatchewan
Tel (306) 966-4433 Saskatoon, Saskatchewan
Fax (306) 966-4461 Canada S7N 5E2
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Received on Thu Apr 1 14:23:48 2004