U of S | Mailing List Archive | alt-photo-process-l | Re: Potentially stupid pt/pd question

Re: Potentially stupid pt/pd question

Potassium oxalate developer by itself won't stain paper. What is probably going on is that your developer is absolutely saturated with ferric oxalate from that it is removing from the print. So when you put the print into the tray of developer, it is bathing in a concentrated sea of ferric oxalate in solution. I would be willing to bet that 1) your developer is old and saturated with ferric oxalate and has a pH at or above 7.0, and 2) your rinse water is slightly basic as well. This would explain the staining on both sides of your paper. So it most likely IS a clearing issue, IMO, that you are seeing, only you are doubling down by soaking your paper in a developer loaded up in ferric oxalate removed from all your previous prints.

Clay, I definitely tell you it's not the ferric that's staining, although
it is the same color (which is why I initially thought it was a clearing

The entire sheet of paper is stained (front and back), not just where it
was coated. The "paper white"

It looks almost as if it spent some time soaking in a tray of coffee.

Camden Hardy