Bleach for black and white prints

SLIMT bleaches are very weak. You can use the same proportions of ferricyanide and bromide, but you'll have to mix a bit stronger bleach. Experimentation is in order

Doremus

koraks said:

It's not very critical

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Great, but please, give a hint where to start
5g/5g per 1L would be ok?

Yup, that should get you started. If that's too slow, double it.

SLIMT bleach is (well, all the papers i've read don't provide clear and definitive informations but are more of a "this thing works, but you have to find it for yourself", so the proposal is) 10 parts of pot-ferricyanide and 3.3 parts of pot-bromide.
The proposal is indeed to use them veeeeeery diluted, probably because the technique is mainly directed towards films and not paper.

Curiously, Kachel writes "DO NOT use potassium bromide with B&W papers. It is not necessary and will in fact cause problems.". No further explanations, don't know if it may pose a problem for the techniques or ruin the paper.

tykos said:

SLIMT bleach is (well, all the papers i've read don't provide clear and definitive informations but are more of a "this thing works, but you have to find it for yourself", so the proposal is) 10 parts of pot-ferricyanide and 3.3 parts of pot-bromide.

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Yes; when I experimented with SLIMT, I made concentrates at these ratios that I could dilute to a working strength SLIMT pre-bleach. When I said the SLIMT solutions are usable here, I was thinking of the concentrates I made. I don't recall if the concentrates were proposed in Kachel's paper; I vaguely recall they were.