[pure-silver] Re: Fishy developer: NOW Triethanolamine
- From: Jordan Wosnick <jwosnick@xxxxxxxxxxx>
- To: pure-silver@xxxxxxxxxxxxx
- Date: Sat, 18 Dec 2004 23:41:37 -0500
John Black wrote:
> Incedintally, I store the Tris/borate as a 5X solution B with 25gm sulfite
> per liter. I recently found that the sulfite at that level slowly craps out
> over 4-6 months and needs to be refreshed. I think I will use some
> metabisulfite in the next batch to help stabilize the sulfite.
John, are you sure that what is precipitating out is actually
sulfite? Borates do weird things with poly-alcohols, and I can
see strange things happening between Tris and borates. Very
interesting idea though. Tris certainly is common in lab use...
Anyway, from what I understand from Pat's writings, the quantity
of Vitamin C in PC-TEA is far more than is needed for developing.
I would say that it probably slightly reduces the alkalinity and
adds buffering capacity to the working solution of PC-TEA.
Ascorbic acid is slightly stronger than ordinary organic acids.
I myself have used PC-glycol for a while. My stock solution is
over a year old and still fine, from what I can tell. I usually
use about 5 g/L sodium carbonate as the activator, which produces
negs with crisp, somewhat fine grain. I'm thinking of trying
others (borax, sulfite) in an effort to reduce the grain a little
bit for scanning purposes.
Jordan
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