From: Joe Portale (jportale@gci-net.com)
Date: 07/09/01-10:57:40 AM Z
The untoned salted paper picture is very fragile. You have raw silver
halides in direct contact with the environment. An option would be to
laquer the print to seal out the air. I do not know how this will effect the
long term image stability. Although I have seen some salt prints from the
1860's that were laquered and they still looked pretty good. The color
change in a photo image is the result of changes in the crystalin strucure
of the image forming grains and how they reflect light. Be very carefull
with selenium, the image can bleach very quickly depending on the paper you
use. I do not recommend selenium, but if you want to give it a try, use no
more than 1/8 teaspoon selenium toner to one liter of water. No more time
than 2 minutes.
your mileage may vary.
Joe Portale
Tucson, AZ
----- Original Message -----
From: "Andre Fuhrmann" <Andre.Fuhrmann@uni-konstanz.de>
To: <alt-photo-process-l@sask.usask.ca>
Sent: Monday, July 09, 2001 7:49 AM
Subject: Re: archival salt prints
>At present I never toned my salt prints because I like their
>characteristic reddish-brown colour, also if I know that without
>gold toning they are not archival.
>Now I am planning a new number of salt prints, and I would ask if
>there is the way to achieve a better stability while retaining their
>original colour.
>Is there any experience in this matter?
>
>Alberto
I also happen to like the rusty colour of untoned salt prints. Being
archival is, of course a matter of degree. Frankly, I do not know
how unstable untoned salt prints really are. From the fact that
virtually all known salt prints of the classical period are toned one
should by no means infer that the reason for toning was to achieve
greater permanence. I have a sizeable collection of pre 20s
photographic literature. The authors when giving recipes for toning
_never_ discuss archival matters but only image colour. The rusty
tone of "raw" salt prints was simply not approved of in those days.
Of course, toning can improve permanence -- in particular, gold
toning certainly does. But this is not to imply that untoned prints
have no reasonable life expectancy. A necessary condition for
reasonable stability is, of course, careful processing and storage.
Instead of gold chloride you may want to try toning with selenium.
At a dilution of 1 + 99 (e.g. Kodak Rapid Selenium Toner) you can
tone for about 2 minutes without loosing too much density. The
resulting image tone is somewhat closer to the raw tone than with
gold chloride toner. But I do not know whether a toning bath at that
dilution and for such a short time can enhance permanence.
André
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