Re: And how sharp I am was/Re: Temperaprint & Gum

From: "Christina Z. Anderson" <zphoto@bellsouth.net>
Subject: Re: And how sharp I am was/Re: Temperaprint & Gum
Date: Tue, 03 Feb 2004 22:03:19 -0500

> I could dig up the article in Photo Techniques from years ago written by
> Ctein, but if I remember correctly, it was some sort of outgassing of the
> paper, esp if glassed. Richard Knoppow will know.

Bronzing of silver-gelatin prints can happen in unsized, baryta or
resin coated prints. This problem is effectively prevented by treating
prints in any of the sulfiding toner or selenium toner.

The problem Ctein described is specific to RC. He also showed that
selenium toning or AGFA Sistan was sufficient to prevent the symptom
in his test condition. And to be accurate, it was ONLY WHEN the print
was framed, not "especially if."

Bronzing may occur as a consequence of a number of different
conditions, and it is not that gas-tight enclosure and light exposure
are necessary to induce bronzing in silver images. Proper toning in
sulfiding toner and ideal storage condition would virtually eliminate
the risk of bronzing problem.

--
Ryuji Suzuki
"Reality has always had too many heads." (Bob Dylan, Cold Irons Bound, 1997)