U of S | Mailing List Archive | alt-photo-process-l | RE: Dark reaction of gum coating

RE: Dark reaction of gum coating

Thanks to everyone that commented about DR. 

A couple of weeks ago I coated two sheets with the same
pigment-gum-dichromate mixture and deliberately placed them inside a metal
cabinet and left them over night. So about 12 hours later I coated two fresh
sheets the same way and then exposed all 4 sheets with a step tablet within
a 20 minute period. I got virtually identical results with all 4 step
tablets. The RH was over 60 and temp was about 75F during the whole period
of dark storage. I was a bit surprised that prints showed no effect of DR.

So I'm not denying DR occurs, I just haven't seen it. Thus I just don't see
how coating a few sheets together in a batch and exposing and processing
within an hour or so can make much difference regardless of the
environmental conditions, which is what I do frequently. And I don't
consider my coating and processing technique to be sloppy as I aim for
consistency since I'm printing with digital negatives.

I suppose everyone's mileage varies as they say,