From: Andre Fuhrmann (Andre.Fuhrmann@uni-konstanz.de)
Date: 06/28/00-08:20:27 AM Z
>... a fellow grad student in
>photography at the University of Delaware, later working at the Library of
>Congress, found that pure selenium did not protect silver as claimed.
>Selenium-toned microfiche was getting just as much foxing as untoned.
>
>Hidemi Yokoto, then a grad student in photography at Tyler School of Art,
>translated Steve's article for Japanese photographers. Word had not reached
>Japan at that point (about 10 years ago) and Kodak was promoting selenium
>toning for archival permanence over there which seemed a pity with the
>existing mercury contamination, etc.
With due respect, Sarah, but thats at best half-true. The one half
is this: Most people (including myself) use selenium at a dilution
and for a time that lead only to a replacement of silver on the
surface of the grain. That is quite enough for imparting the kind of
colour change that one expects from selenium toners. The other half
is that selenium is a much more stable metal than silver. Thus, if
you tone with selenium you will always have _some_ archival
advantage. If you tone with a strong solution for a sufficient time
you will get a print as archivally permanent as you can reasonably
wish for.
Andre
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