Re: Selenium-toning Van Dyke Brown prints
From: Judy Seigel <jseigel@panix.com> Subject: Re: Selenium-toning Van Dyke Brown prints Date: Wed, 27 Sep 2006 02:37:44 -0400 (EDT) > Any formulary (like Photographic Facts & Formulas, or probably Steve > Anchell's Cookbook, will have the hypo alum & carbamide, which are > classics.) Hypo alum toner loses density even with silver gelatin prints and it's probably not a good choice for VDB. It's also a sulfur toner, not selenium. Thiocarbamide is a misnomer, or at least old name that is not used in chemisty today. Thiourea is common name. > Selenium powder is poison, but IMO they make too big a deal about this. > Don't breathe it, is all -- oh, and don't drink out of the glass (pyrex > coffee maker) you've boiled it in. More important than "don't breathe it" is that you should know what to do when you spill it, for example. > And about bubbles: One drop of Kremer 78600 Defoamer in a liter or so of > 3% warm gelatin removes the bubble problem entirely with no down side. > That's ONE DROP ! In my experience with this defoamer is that it increases coating defects on the layer that's coated on top of it.
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