RE: Want more glow in Pt/Pd

I am not qualified to speak to the main issue but I am qualified to discuss
shellac. Although the term refers to both natural and synthetic forms of
shellac, all are very poorly suited to your intent. Shellacs absorb
moisture with resultant milk-like staining and deterioration. Varnishes do
not have that problem and may be tried in very thin layers with careful
drying between applications. But they have their own problems. I have used
bowling alley wax and renaissance wax and concluded that I do better without
any coating. Joachim

-----Original Message-----
From: Judy Seigel [mailto:jseigel@panix.com]
Sent: Wednesday, November 10, 2004 5:15 PM
To: alt-photo-process-l@sask.usask.ca
Subject: RE: Want more glow in Pt/Pd

Sandy King wrote:

>> I have tried various things to recapture the *wet* look of Pt./Pd.
>> prints, including spray coatings with Crystal Clear Acrylic, surface
>> coating with Gamblin and Renaissance Wax, soaking in Liquitex Acrylic
>> Gloss Medium, etc. but the results with these products, though they
>> give a little snap to the print, fall short of what I would like to
>> see.

In one of his early articles about gum, Demachy described applying "Vernis
Soehnee" which, he said, restored the depth of the wet print without
glazing the paper whites. I tried to find that formula for years.. aided,
among others, by Gene R. of this list, who took it up with his very
obliging research library. I've also found several references to it in old
painter's recipe books, where it's called a resin. Since alcohol is
the solvent, it figures to be shellac or shellac plus, but my experiments
with shellac (of various kinds, including "white") were not successful.

The best I found for the purpose so far was a diluted gum arabic (about
1:1), sheeted down the paper (method of application is important). Also
some of the newer alkyd varnishes (Gamblin, eg) are promising... On the
other hand, for gum printing, the best strategy may be simply multiple
coats of sufficient intensity of color that extra would be too much.

However, Sandy, with your language and research skills, you may find the
answer... (tho there's also the possibility that Demachy was overstating
the case...and/or that it wouldn't work on a gelatin size, since he did
not add size to paper, or if so, used starch.)

thanking you kindly in advance,

Judy
Received on Wed Nov 10 18:53:48 2004