Re: Toner
jwhite@microprose.com
Tue, 28 Apr 1998 12:32:52 -0700
At 12:44 PM -0400 98/04/27, Carl Weese wrote:
>Bob,
>
>The really short take is this: toning "guilds" the silver in your print
>with another substance.
>
>Almost any other substance is less susceptible to deterioration than
>silver (how often did your mother have to polish the silverware? Every
>time it was to be used, right?) so the print is more archival if the
>silver is treated. Selenium is often used when the appearance of the
>print should remain the same but a protective treatment is desired. With
>some papers selenium will also make a substantial visual effect. Gold
>toning changes color and greatly enhances permanence. Sepia toning is
>usually done primarily for the visual effect but I think it has some
>slight beneficial effect for permanence. You can even tone with
>platinum, for enormous archival effect, but it would be easier and
>cheaper to make a platinum print in the first place.---Carl
--------------
>The most archival methods are sepia and selenium toning. Gold is not as
>good and platinum toning, which replaces silver for platinum, leaves a
>significant amount of silver which, with Ilford papers anyway, is more
>vulnerable than straight, untoned silver prints.
>The above was verified empirically by Ilford back in the days when "we"
>were working on a new paper with superior archival qualities -later named
>Galerie.
>Luis Nadeau
>NADEAUL@NBNET.NB.CA
>Fredericton, New Brunswick, Canada
>http://www3.nbnet.nb.ca/nadeaul/
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Is this true of both sulfide and thiobarbamide (thiorea) sepia processes?
-J. White