RE: Determining SPT with gum Was: Gums a la Demachy and Puyo from Loris Medici on 2006-07-12 (July 2006 Alt-Photo-Process-L@usask.ca)

From: Loris Medici <mail_at_loris.medici.name>
Date: Wed, 12 Jul 2006 23:52:37 +0300
Message-id: <20060712205258.8F16D76DF1@spamf4.usask.ca>

Thanks David... One should look to density in a relative manner; that is as
high as the actual coating solution permits... Not absolute density.

Regards,
Loris.

-----Original Message-----
From: David & Jan Harris [mailto:david.j.harris2@ntlworld.com]
Sent: 12 Temmuz 2006 Çarşamba 13:41
To: alt-photo-process-l@usask.ca
Subject: Re: Determining SPT with gum Was: Gums a la Demachy and Puyo

Loris

That is interesting. I agree that with the visual approach it is easy to
choose too great a SPT.

With gum, I get dichromate stain at exposures lower than the Dmax exposure
so I chose my SPT based on a level of dichromate stain that is easily
cleared. This way I can stop my colours from getting muddy. I usually do gum
over cyanotype so I'm not too concerned about high density.

David
Received on 07/12/06-02:53:07 PM Z