Re: cyanotype failure to clear

[Judy Seigel <jseigel@panix.com>]

On Wed, 15 Aug 2001, Shannon Stoney wrote:

>  Recently the cyanotypes I've been making have not been clearing.  It used
> to take five minutes of washing, with 4-5 changes of the water in that time,
> to get all the yellow out, but now it takes longer, and sometimes I don't
> realize it didn't clear till the print is dry and the back of the print is
> blue.  What could cause this?  I wonder if it has to do with the solutions
> aging.  They have been around since May.  Should I make up new solutions?  I
> am using the same paper as always.


Shannon,

Is your workspace air conditioned? In hot weather cyanotype can fog
rapidly before exposure.... does the emulsion start to look blue or anyway
quite green when you put it under the negative?  How long are you waiting
from coating to exposure?  If it's sitting more than 15 minutes in really
hot humid environment, that could be the problem. Are you coating a bunch
of papers & leaving them to sit?

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 ?

As for age of the emulsion, that alone isn't your problem, in fact 3-4
months is actually quite fresh. I've used 5-year old emulsion without a
problem in clearing, tho it had lost speed.

Judy

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