From: Sam Wang (stwang@clemson.edu)
Date: 07/04/01-07:45:40 AM Z
Shannon,
Yes, the color is probably from humidity, especially when combined 
with heat with long exposure. Most of it goes away with a longer 
soak. Otherwise it is permanent.
Use a small fan to dry the paper before exposure and to remove heat 
from the UV unit.
Sam
>    I made some cyanotypes today from some really dense negatives.  At
>least, I think they must be really dense because they look dense and they
>took 30 minutes to expose to get anything close to Dmax under the black
>lights.  (I don't have a densitometer here in TN.)  Something weird happened
>on two of them:  in the lighter areas, there is a sort of lilac color,
>unlike the light blue of the normal light areas.  What causes this?  The
>other variable, besides the long exposure, might be the really, really high
>humidity--about 95% at night.  My paper fogs while it is drying after I put
>the emulsion on it. (And it takes a long time to dry.  I help it along a bit
>with the hair dryer sometimes.)  Is the lilac color a symptom of fogging?
>
>--shannon
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