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Re: Pyro ABC+

Martin,
reading about your problems with the A solution of ABC+ and following your
conversation with Carl I have to agree him that something seems to be wrong
with your Pyrogallol. The A solution isn´t in such high concentration that
precipitates will be formed at room temperature normally.
Maybe your Pyrogallol is not in such quality we need ,it can have an unknown
amount of by-products (5-20%) depends on its quality grade. This by-products
may react in the  A solution and form the precipitate - and there must be
some reactions in the A solution because it should be first used some days
after mixing - I call this a ripening-process.
You should call Phtographers Formulary for another sample of Pyro, tell them
your problem.

I use the ABC+ formula like 1+2+50 @72 degrees for 6,5 min (Tri-X with ISO
320)

maybe this settings can solve your problems, too.

Greetings
Harald

Harald Leban
hleban@telering.at
Austria / E.U.


-----Ursprüngliche Nachricht-----
Von: "Martin Salowey" <mnspeebs@castle.net>
An: <alt-photo-process-l@skyway.usask.ca>
Gesendet: Samstag, 28. April 2001 23:15
Betreff: Pyro ABC+


> Hi All,
>
> I have been working on standardizing Tri-X sheet film processing times
with
> the ABC+ Leban Formula diluted 1:2:75 @72 degrees F in a Jobo Expert drum
> with the rotation set at 4.
>
> I have a couple of questions to get me headed off in the right direction.
>
>
> 1. Should fresh stock solution A after sitting a few days in a room at
> about 68 degrees F form a precipitate? I went to process some film this
> afternoon and was shocked to find my fresh stock, mixed less than a week
> ago, has a fuzzy precipitate (looks kind of like pyro crystals). I am
> assuming it is the pyro since the solution is rather saturated, but does
> not seem to want to dissolve when gently heated in a bain marie. Anybody
> else ever have this problem? The pyro was purchased in 1 lb. quantities
> from Photographers Formulary.
>
> 2. I realize that densitometric evaluation is really only a point of
> departure with pyro but would like to see if my results are heading in the
> right direction. (Mr. Wesse are you out there?) The densities are for a
> given exposure(zone) and read for both neutral and yellow (B) channels.
> (Exposure Neutral/Yellow) These tests were processed in ABC+ 1:2:75 @ 72
> degrees F for 8.5 minutes in the 4x5 Jobo expert drum at a rotation of 4.
>
>
> 1. fb+f   .12/.27
> 2. Zone 0 .24/.45
> 3. Zone I .32/.58
> 4. Zone III .45/.87
> 5. Zone V .68/1.18
> 6. Zone VIII 1.31/2.06
>
> Thank you in advance for your input.
>
> Marty