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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