From: Judy Seigel (jseigel@panix.com)
Date: 06/13/02-01:24:25 PM Z
On Thu, 13 Jun 2002, Witho Worms en Jorien van Santen wrote:
> Hello Judy,
>
> Can you tell me how to make this chromium intensifier.
My formula says Kodak In-4
===========================
STOCK SOLUTION
water -- 75 cc
potassium dichromate -- 9 grams
hydrochloric acid -- 6.5 cc
add cold water to make 100 cc
To use: one part stock solution to 10 parts water. Mix just enough to
cover the negative in a small tray (you can bleach a few negatives with
that if you want), then discard.
Bleach negative thoroughly at room temperature, then wash five minutes.
Redevelop fully, agitating about 5 minutes in artificial light or daylight
(not sunlight) in Dektol 1:3. Be sure to redevelop the full 5 minutes for
full intensification. (Don't trust your eye -- it can look fully
redeveloped sooner.) If necessary, clear orange color with a pinch (1/4
tsp) sodium sulfite or potassium metabisulfite in tray of water. Wash,
photoflo to prevent spots, dry.
Note: I've used ammonium dichromate when I had no potassium. I don't think
it matters a lot. I also don't think exact amounts are critical (like
don't worry about the 1/2 cc), but I'd assume pyro would NOT intensify
this way. Doesn't acid kill pyro? (Or is that the other way around?)
Whether the residual silver would intensify enough to make up for loss of
pyro tone -- quien sabe?
If you have a current formulary you might check what they say -- Anchell,
or Hirsch, or whatever. This one is, as I recall, from Photographic Facts
and Formulas, or wherever I got it 20 years ago.
Judy
>
> Is it possible to intensify Pyro or Pyrocat developed negatives by this
> method ?
>
> Witho
>
>
> ----- Original Message -----
> From: "Judy Seigel" <jseigel@panix.com>
> To: <alt-photo-process-l@skyway.usask.ca>
> Sent: Thursday, June 13, 2002 3:19 AM
> Subject: Re: Selenium Intensifier
>
>
> >
> >
> > On Wed, 12 Jun 2002, Istvan Bibo wrote:
> > > >
> > > I used Ilford Selenium toner (IT-3) to boost negatives and the more
> > > dilute solution (1:20 vs. 1:10?) resulted more added density.
> >
> >
> > For what it's worth, I got significantly more intensification on lith film
> > and Agfa n31p with chromium intensifier to start, followed by selenium
> > toner. (Kodak doesn't sell chromium intensifier any more, but the formula
> > is easy to make as long as you have potassium or ammonium dichromate.)
> >
> > The twice intensified film was not only notably denser by densitometer
> > than either intensifier alone, it got quite a reddish tone, which I assume
> > would have had a further actinic effect.
> >
> > Judy
> >
> >
>
>
>
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