Grafist@aol.com
Date: 03/18/03-06:56:26 PM Z
In a message dated 18/03/03 14:49:35 GMT Standard Time, zphoto@montana.net
writes:
> I also tested sensitizing the paper, drying, and putting a layer of
> pigment and gum on top (one of Wall's ideas) and it worked--weird. Didn't
> expect it to, thought the layer of top paint would all swoosh off, not
> conceiving how it would intermingle with the layer of dichromate below, but
> it did. Go figure.
> Chris
........................................................
Hi again, Chris,
Please excuse my butting in on your posting to Dave
but I have also experienced this which seems to be because the sensitized sub
coat, altho` dry, tends to imbibe or suck in the gum/pigment top coat when
applied. The UV exposure obviously penetrates the unsensitized top coat to
harden the dichromate beneath. I learned some time ago that UV is classed as
``radiation`` which acts in a rather more positive way through the mask of
the pigment than non actinic light would. Here, again, I am mindful that a
sizing coat might have been used which also could have something to do with
why this worked.( ? )
A good starting point for further research. Glad you brought this to light.
As ever. John - Photographist- London
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