Eric,
I add 1 gram oxalic acid to 50 ml ferric oxalate solution GLSmyth@ari.net (27%) and
somtimes use hydrogen peroxide as a contrast agent. However, I have not
observed the solution to be a "bright emerald green". What is meant by
"a little help"? I would appriciate if you would please send your
formula.
Also, what do you mean by 30% hydrogren peroxide. The type purchased
from a drug store is typically 3%. 30% can be purchased from a chemical
supplier, but caution must be used since it is a combustion and
explosion hazard. Did you mean that to 20 ml ferric oxalate you add 10
ml of 3% hydrogren peroxide ? If so this would seem to be far too much
contrast for a properly processed negative for the Pt/Pd process. But
maybe not.
Jeff
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