From: Richard Knoppow (dickburk@ix.netcom.com)
Date: 06/23/00-12:01:23 PM Z
At 02:30 PM 06/23/2000 +0200, you wrote:
>Hi All!
>
>After the first messages on salted papers on Wednesday I felt an itch
>to try it out. So I coated Arches Aquarelle twice with salted (3%)
>gelatine (2%) and after thorough drying applied silver nitrate 12%
>twice. What I found left mixed feelings. The images printed out
>vvvvery nicely but after fixing (5% hypo) they were reduced to very
>flat images indeed. More overexposing didn't help the flat
>appearance. So I suppose that the process is for _extremely_ hard
>negs only. and indeed with my hardest negs I got some acceptable
>results -- but only after I watered down the hypo to 2-3% where I
>left the prints for 8 mins. Now I naturally wonder how stable the
>images will be. Frustration came to a climax when I perused my
>beautiful Nadar book (published by Schirmer & Mosel). The Nadar
>prints are so stunningly beautiful with their luminous shadows and
>bright but well-separated highlights! How on earth did he do it? I
>conclude that the salted paper process has very great potential but
>is also very far from being fool-proof. One possible source of my
>ill-success is perhaps the use of household salt. Perhaps it is too
>impure for the purpose, leading to chemical fogging. But then, how
>pure was the salt Nadar used in the 1860s?? The salt I used
>contained also some iodide which, I guess, enhances the tendency to a
>warm brown tone.
>
>As to the comparison with vandykes, I side -- as yet -- with Judy.
>It strikes me as a much simpler process, easier to control, better
>suited for nearly normal negatives and, not to forget, cheaper. As
>to their permanence: As I write this I look at a test vandyke stuck
>to my window 7 months ago. I covered half of it with black carton
>(probably _not_ acid-free), the other half faces the sun for a couple
>of hours every day: as yet no visible change. That indicates a good
>deal of permanence, though, of course, we may have to wait another
>300 months to pass a judgement with more confidence.
>
>Andre
>
It seems to me the flat results are due to bleaching by the hypo. Hypo
will partially dissolve the very fine silver particles of photolytic
silver. With POP paper the same sort of bleaching takes place unless the
image is toned with Gold _before_ fixing. Gold toned images won't be
reduced by the fixer.
Selenium could be used as an alternative to gold but I don't think Kodak
Rapid Selenium Toner will work, its about 25% ammonium thiosulfate, and it
will stain halide (1:9 KRST is a standard test for complete fixing of
conventional paper).
As far as permanence, gold toned images should be very long lived.
---- Richard Knoppow Los Angeles,Ca. dickburk@ix.netcom.com
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