Re: Removing Cyanotype Solution from a Stouffer Wedge

Why Sistan? If you could decompose hexacyanoferrate to free
ferric/ferrous ions (ferrous ions will eventually be oxidized by air
to be ferric), thiocyanate would make soluble, but blood-colored
complex. But it seems to me that acid/chelate mix like glycolic acid
and EDTA would do. If you have CLR Rust Remover, try that, because
it's supposed to be a blend of glycolic acid, citric acid and sulfamic
acid, with lots of surfactant. If you have some EDTA, throw that in too..

BUT - I would make small strips of fixed out 35mm film base, dried,
similarly contaminated with cyanotype sensitizer and test treatments
on them first. Do it soon - if Prussian blue is formed in/on your step
tablet, that may be it and only your credit card could solve the
problem.

--
Ryuji Suzuki
"Well, believing is all right, just don't let the wrong people know
what it's all about." (Bob Dylan, Need a Woman, 1982)