Re: POP process

From: Loris Medici <loris_medici@mynet.com>
Subject: Re: POP process
Date: Mon, 08 Nov 2004 19:03:47 +0200

> Is there any selenium toner fomula that doesn't incorporate sodium or
> ammonium thiosulfate so that we can use it "after fixing" but without the
> fear of "further" image fading?

Ok, I took it in a different way - gold toning in POP reduces the
image density loss by fixation, so I thought he was looking for a
selenium toner that could be used before fixation. That, I don't think
is possible. But thiosulfate in KRST is not much when you make a
working solution, and I don't think that would bleach the image
further. But selenium toner can be made without thiosulfate, for
example Kodak formula T-55. Thiosulfate is in KRST to make the toning
action rapid. I also make a toner that contains both selenium and
polysulfide, which makes dark chocolate brown to purplish brown with
silver gelatin prints (and it also gives very good archival
protection).

> ITOH, isn't powdered Selenium quite poisonous / dangerous?

Yes, I wear face mask, dust mask, lab coat and gloves when handling
it. But I only have to make a small quantity of concentrate solution a
couple of times a year because my toners have large processing
capacity and I reuse the solutions.

--
Ryuji Suzuki
"You have to realize that junk is not the problem in and of itself.
Junk is the symptom, not the problem."
(Bob Dylan 1971; source: No Direction Home by Robert Shelton)