I need to add a coda to one of my previous messages on testing J&C Classic 200 film. It turns out that the digital thermometer used to measure the temperature of the developer and the water bath was low by about four degrees. So what I thought was 70 degrees F was in fact 74 degrees F. Adjusting my previous recommendation I would now suggest adding about 15-20% time to the previous time recommendation and have adjusted the times accordinly below.
For development of J&C Classic 200, using Pyrocat-HD 2:2:100 at 70 degrees F, for AZO and Palladium printing, use the following times.
SBR 7.5 4:15 minutes
SBR 7 6:00 minutes
SBR 6 8:30 minutes
SBR 5.5 10:45 minutes
Negatives for silver printing should be developed for about the same times as above, but using the 1:1:100 dilution of Pyrocat-HD.
For clarification, the above times in the lighting conditions described will produce an effective negative density range of about 1.6 for palladium printing using UV light, and an effective printing density range of about 1.30 for AZO printing. The dual purpose nature of the negative is of course due to the stain, which functions as a highly efficient filter to UV light. In measuring the difference between a blue channel reading and a UV channel reading I have found that there is a much greater difference between these two readings with Pyrocat-HD than with PMK or Rollo Pyro. This is due to the fact that the yellow/brown stain of Pyrocat-HD provides greater actinic filtration than the greenish/yellow stain we usually see with PMK and Rollo Pyro.