Sandy King (sanking@hubcap.clemson.edu)
Tue, 06 Jul 1999 15:33:34 -0500
Increasing the amount of the A solution would be a good solution for PMK
to boost contrast because the amount of developing agent per liter is
already so small that you get developer exhaustion, which makes it a
compensating developer. So a 1:2:50 solution makes sense. Rollo Pyro, on
the other hand, already contains so much developing agent that you are not
going to get exhaustion, even with long development times, so the best
solution here is to increase the activity of just the accelerator, either
by increasing the amount of sodium metaborate or changing to the more
active carbonate.
Sandy King
>>Pyro is by nature capable of high contrast development so there are
>>definitely ways for you to get to N +3 or N+4, even with a DR of 2.0, and
>>still get the stain. Basically you need to increase the pH of the working
>>solution to make it more active. Try doubling (or even 4X) the amount of
>>the B solution of Rollo Pyro. If your standard is 1:2:50, try 1:4:50 or
>>1:8:50.
>
>What would happen if you changed the amount of the A solution? I've heard
>of people going from 1:2:100 to 1.25:2:100 or 1.5:2:100. What effect would
>that have?
>
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