From: Breukel, C (HKG) (cor@lumc.nl)
Date: 01/28/02-06:01:59 AM Z
On the T55 formula: this toner doesn't contain amoniumthiosulphate as
Kodak's RSE, as has been said before. One possible reason might be that
the diluted T55 (which I mean more than 1:4) is not stable (there is a
strong deposit of, I assume Selenium, it is reddish/black, on the wall
of the bottle after 1 week or so). KRSE is stable in dilution.
Cor
Judy Seigel wrote:
>
> On Sun, 27 Jan 2002, Andre Fuhrmann wrote:
> > ... As the toning process progresses, the concentration of
> > sodium sulfite in the solution increases. I find it hard to believe
> > that this is a dirty trick that Kodak and others play to make ALT
> > processes harder. Question to our resident chemists: is there a
> > practicable way of producing solutions of selenium fit for toning
> > such that the solving agent would not also dissolve silver to some
> > degree?
>
> Andri, your reasoning is way over my head, but I have one advantage over
> you: I've done the T55 & the T56. The selenium isn't used alone, in the
> first it's with sodium sulfite, the second with sodium sulfide.
>
> I gather you're saying it *needs* the fixer or else why is it there? I
> could speculate on a number of reasons, such as to be ON THE SAFE SIDE..
> many old formulas say refix after toning just IN CASE there's some
> leftover silver halide, not that that would matter, but it could change in
> appearance with time. Meanwhile, I would NEVER NEVER NEVER accuse a
> corporation of being sensible.... (Or why would they make electric alarm
> clocks without a lit dial?) Their decisions are what the men in suits
> consider correct, safe, proper, profitable, etc.
>
> In any event, in the old Brovira I was using, no color change with KRS,
> the T55 & T66 made lovely purply brown-blacks... and did not to my notice
> do anything bad, like fade, or bleach. Is that what we're talking about?
>
> But that was silver gelatin. I only had a few drops left when I began VDB,
> only enough to test a scrap. Looked good, as I recall, but no way
> conclusive. and I never got around to mixing more -- too many other games
> to play.
>
> Maybe next time....
>
> J.
This archive was generated by hypermail 2b30 : 02/15/02-11:47:41 AM Z CST