Re: cyanotype failure to clear

[Judy Seigel <jseigel@panix.com>]

On Sat, 18 Aug 2001, Shannon Stoney wrote:
> None of this has changed much in the last month:  I coat the night before,
> store the coated paper in a box in the refrigerator, and remove it about
> half an hour before starting to print.  The emulsion looked ok before
> printing.  It was actually hotter and more humid about a month ago than it
> is now.

Shannon, sounds totally mysterioso at this point... I would suggest
being sure to keep flipping the print in the developing water... Leaving
it still and/or face up means emulsion may not be adequately sluiced away.
As for why it didn't happen before... ????????????

Maybe your luck has changed.  Maybe it did somewhat but you didn't notice.
Maybe the reason will come in the fullness of time.... I'd suggest ANYWAY
getting a small digital room temperature & humidity guage... About $35
from TALAS. It's possible humidity has crept up in studio but gradually,
like the rat in the boiling water?  Or test the fridge... Or maybe that
box in the fridge got worn out... But whatever, I find that RH gauge
(notice I'm hedging my bets on that spelling) in studio is terrific on
general principles. Also fascinating to equate your discomfort with the
RELATIVE humidity. And to see how it creeps up at night when you've got
the lights on -- even fluorescent lights !!!

As for change in the water -- sounds as likely as anything. Not
necessarily the pH, maybe organic matter has some other chemical effect.
Try a wash in distilled ???? (Which generally speaking I found gave less
density, but this is a TEST.)

yours in science... which suggests another explanation... the paper
reports that the ALPHA of science is now believed to have changed. If so,
maybe the alpha of cyantific has also changed ????

Judy



>
> >
> > If everything above is negative -- are you washing the print face down,
> > flipping it over from time to time?  Has anything in the lighting
> > conditions -- either over the sink or in the drying cabinet -- changed?
> > Or maybe in summer the water coming in is warm enough to cause problems ?
>
> I don't always wash the print face down, but I wasn't doing this before,
> either, and never had a problem.  Lights are the same.  Water temperature
> probably about the same.  The only thing I can think of is that we had a
> huge amount of rain recently, and a lot of sediment washed into creeks and
> lakes, and I wonder if the ph of the water has changed perhaps?  Would that
> affect the clearing time?
>
> --shannon
>
>