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View Full Version : Printing, Bleaching, and Toning Kallitypes



Fragomeni
8-Mar-2011, 12:55
I have a question that I haven't yet had answered and I'd like to try to figure it out before I buy the chemicals. If anyone can offer any insight it would be greatly appreciated.

When printing Kallitype, can you apply Potassium Ferricyanide or some other bleaching agent to the print to raise tones and then tone the print without the raised toned being subdued? My assumption would be that you can because you working with a silver process which should behave like any other silver process in which tones can be bleached. My concern is whether or not during toning, the bleached tones will retard back to their previous tonality when the toning metals (Platinum) replace the silver metals. I don't think this would happen but I'd like to verify it.

A little background into my question. I was just printing Cyanotype with the intention of toning to produce black Cyanotypes. I printed the images and selectively bleached (using the bleach in Bostick & Sullivan's Cyanotype Toning Kit) highlights and some midtones (effectively dodging) to place the tones exactly where I wanted them. The blue Cyanotype then looks perfect except it is still blue so I tone using Yerba Mate (a South American tea which will tone without staining the paper base) and the print goes black. The problem is that the tannins in the toning solution bind to the residual metal salts in the areas that I've bleached. The areas are bleached and are visually lighter but the metals are still there and the tannins bind to them and bring them right back down to where they were previous to bleaching. This is what I want to avoid with Kallitypes. So, after bleaching will toning tone the print values where they are after bleaching or will toning cause the bleached tones to retard to the tones that they were before bleaching?

Thanks for any help.

-Francesco