From: Judy Seigel (jseigel@panix.com)
Date: 07/10/01-12:37:07 AM Z
On Mon, 9 Jul 2001, Shannon Stoney wrote:
> I am getting these tiny white spots on my cyanotypes all of a sudden. It's
> as if in some places, the emulsion is not sticking to the paper. I don't
> think it's dust on the glass as I'm pretty careful to clean the glass. This
> problem just suddenly appeared this week. The only possibilities I can think
> of is that it might have to do with the solutions aging, or being exposed to
> hot weather, or the intense humidity affecting the way the emulsion is going
> on the paper. Any ideas?
Did you change paper or start a new batch of the "old" paper? Some papers
give those white specks (eg BFK) because there are tiny fibers standing up
that mask the paper under them, so it doesn't expose. Try checking the
paper with a loupe.
Are the specks regular (which points to the paper), or irregular, which
may point to something like dust... Or is there a possibility of some kind
of contaminant? For instance if your coating brush gets onto a counter
with gunk on it, that can contaminate rest of the paper... but hard to see
how it could get into your basic A & B solutions.
What does the solution look like? Any specks in it?
One other possibility comes to mind -- if your A solution has gotten mold,
and the mold has gotten broken up and dispersed through the solution,
might conceivably leave white spots. You could try filtering both
solutions (coffee filter) & see if that clears it up.
FWIW, aging and heat do not (in my experience!) bring on white spots, at
least not in cyanotype (no telling about people).
Judy
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