The polyurethane substrate was improved by brushing more quickly, so that
it was still liquid enough to level, not trying to make strokes neat at all,
which slowed things up enough to be self defeating. Also, as suggested,
the mineral spirits thinning the poly were omitted. Working more quickly
thinning wasn't necessary.
The Liquid Light emulsion was thinned with Dektol one part in 10, as per
suggestion;and the idea of putting it in cold water bath before
development (or was it after development? whatever) also made big
difference --either that or lack of thinner in poly, or both, removed
tendency to peel.
Two coats of emulsion were OK -- it could have been three -- but that
would have taken longer than forever. And incidentally, the exposure time
on my Durst 4x5, enlarger from hell with the cold light head, was one
half hour, plus one half hour edge burn. Each of them probably could have
been 45 minutes! (This on negative with top highlight at 1.3.)
Development in Dektol 1:2 was 4 minutes, & I suspect could have been 5.
There was also the discovery that what looked like terribly streaky
grooves in the applied emulsion when the first "print" was finished last
night, were much better this morning when the gelatine was completely dry
& had shrunk.Still visible, but in that large scale not so obtrusive. (They
wouldn't be a problem at all on paper or absorbent surface.)
Application by spray would no doubt have been better, but results now good
enough -- and given the small space, lack of hood, crowded quarters in
darkroom, etc. spraying didn't seem practical.
If more refinements develop, so to speak, I'll report. Meanwhile thanks
again from the cellar.
Judy