Re: 2 cyano formulae
On Sat, 23 Aug 2008, Jack Fulton wrote:
Thanks Jack... I think meanwhile, the point getting lost in the discussion about "degradation" is that no matter what ingredients you use, nut hulls, battleship hulls, chinese voodoo tea, et al... if you just soak the print in it, the whites will ALSO be stained... which, no matter what you call it, is a form of "degradation."We cannot let a day go by w/out recognizing "The World Journal of Post-Factory Photography", which, in Issue #7Speaking of toning cyanotypes
Real "toning" (not staining) of cyanotypes requires a bleach (either before or after the tannic soak, which for cyano would be one of several alkalis). Procedures vary -- the ones Jack gave, if they're from my article, were among those that worked best.
My classes loved cyano toning and some of the A++++ students titrated the variables very finely, making UPgraded cyanotypes. Depending on your timing, depth of the original, and yr general print "hygiene", you can get split tones, reddish brown and/or purplish, and/or near black, etc. etc. Of course just staining, say, dipping in tea (which contains tannic acid), could soften a strong blue, if that blue bothers you -- but of course that stains the paper whites, softening contrast as well... Real *toning* (actually a form of bleach & redevelop), can leave purest paper whites, and turn middle blues into intermediate tones (for even *more* differentiation).
Now this discussion reminds me that once after a workshop that we could hardly finish I decided the curriculum was too full & should be cut. I suggested omitting cyano toning, but, to my surprise, there was an outcry of "NO !!! That was the most fun."