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

From: Katharine Thayer <kthayer_at_pacifier.com>
Date: Wed, 12 Jul 2006 15:43:31 -0700
Message-id: <92EE2FF7-644C-48BB-A10D-AC3F3232D860@pacifier.com>

>
> -----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.

Oh shoot, another hypothesis down the tube. I had always wondered if
the reason I never get dichromate stain is because of the photoflood
light, but if you get dichromate stain with the photoflood, there
goes that idea. Oh well!
Katharine
Received on 07/12/06-04:42:36 PM Z