That's not correct. Gelatin sizing is only a problem in the context of pure platinum (or very platinum heavy pt/pd ???) process, and that's when printing over a gelatin size. You <edit: can> use gelatin size safely over a finished / successful pure pt, pt/pd or pure pd print, if what you want is to put something else (gumover layers for instance...) on it.
Thanks for the information!
I have been trying to work with gelatin sizing over the last few days and I am getting a strange speckling effect on the paper. Is this because of improperly made sizing or not soaking the paper long enough prior to printing or possibly something else?
I would be interested in learning what this could be.
If you mean a straight palladium print that's pretty much correct. Most people don't size their paper for iron based printing. Dick gave you good advice. If you mean gum over palladium then yes a gelatin size is applied over the palladium image.
It is a while now thaT I have done them, but New Chrysotypes (Mike Ware's process) print excellently on heavily sized paper, and can be printed over very well.
They are of course somewhat more complex than Pt/pd.