Re: drying cyanotype: LS

Judy Seigel ( jseigel@panix.com)
Sun, 05 January 1997 8:28 PM

On Mon, 6 Jan 1997, Luis Nadeau wrote:
> Printing
> When after drying? If you hot dry a print and then wait hours to
> expose your print you can assume that the paper fibers are now back
> to normal RH.

Luis, I'd expect the *paper* would be back to "normal relative humidity,"
but the *emulsion* is not necessarily returned to the status quo ante. At
least I've always assumed that changes induced in the emulsion by heat
were probably permanent... and I have, rightly or wrongly, assumed it was
effects on emulsion that changed "speed" etc. of the paper.

For testing purposes, BTW, I do try to standardize drying time (1/2 hour
for gum strips), but I use "available" RH, since I have a studio, not a
NASA lab. In making an actual gum print, however, such variables are
easily dealt with by varying temperature and/or time of development. ( Eat
your heart out, platinumists!)

A propos of which I'll mention that a lot of what Charlie Palmer
accomplishes with his mask-erade is readily done by selective brushing, or
even a few drops of water judiciously loosed over a gum print. (See
above.)

Judy

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