Quote Originally Posted by mr.datsun View Post
Gerald, Thank-you. So what I need to work out now is whether D76 is similar enough to D94a once the sodium thiosulfate is added to produce similar results? I'll find the formula and post them.

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afaik, DTOD is the hypo for which we use the sodium thiosulphate. ....

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Wrong! DTOD is HOCH2CH2-S-CH2CH2-S-CH2CH2OH (1,2-di(2-hydroxyethylthio)ethane). It was substituted for 9.1 ml of sodium thiocyanate (51% solution) (not thiosulfate) to turn D-94 into D-94A.

D-94 is very different from D-76. D-76 does not have the energy to make a good reversal first developer, although variants of it have been used for some special purposes. Reversal first developers are normally high contrast negative developers, like D-19, with some thiocyanate added as a silver solvent to keep the highlights clear. D-67 is another popular first developer. It is simply D-19 with 2 g per liter of potassiun thiocyanate added. Dektol is fairly close (but not the same) as D-19; diluting it 2+3 and adding thiocyanate may (but only may) work decently.