Quote Originally Posted by Ray Bidegain
I would like to a technical question, of those of you that are using pyrocat HD for you platinum printing. I have been using it for a bit and really like the fact that my negatives for platinum print well in silver as well. The issue I am having is that the printing times for the platinum are way too long. In the area of 30-60 minutes. I have a home made light box that prints a TMY D-76 neg in 8-10 minutes.

Ray Bidegain
There should be very little difference in printing times between well exposed and properly developed negatives developed in Pyrocat-HD and a non-staining developer such as D76 or Xtol. Printing times are determined by shadow density, and since stain is proportional to silver density, lowest in the shadow areas and highest in the highlights, there should be little difference in density in the shadows between a negative developed in Pyrocat-HD in contrast to one developed in a traditional developer.

My own negatives developed in Pyrocat-HD print in about 8-10 minutes with a bank of BLB tubes, with the tubes about 5" from the printing plane. High speed films (HP5+, Tmax 400, etc.) develop more B+f than slow and medium speed films and for this reason may need slightly longer development times. Very long exposure times (and 30-60 minutes is quite long) could result from several conditions.

1. Over-exposure. If you over-expose by one stop you more than double your printing times.

2. Use of slightly fogged film. As film ages, or if left in high heat for too long, it develops a higher B+f from fogging. This can easily add a stop or more to your exposure times with a staining developer like Pyrocat-HD.

3. Too much agitation in development can also lead to higher B+f levels.



Sandy King