[quote="Annie"]Some further ponderings about Pt/Pd toning......


Oh ....and just curious why we were trying to do this substitution thing in the first place?


Annie,

My interest in the substitution was to obtain greater permanence of kallitype prints. By replacing silver metal, whcih oxidizes readily, with gold, platinum or palladium you should in theory have a print that will be almost as permanent as straight pt/pd prints. Some of my bleaching tests seem to confirm that this is indeed the case.

I think most people would agree that all silver prints, be they salted paper, albumen, kallitypes or contemporary silver gelatin, should be toned for greatest permanence.