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Response to Divided D-76 which formulation and times

from Pete Andrews (p.l.andrews@bham.ac.uk)
On a purely theoretical note: I can see absolutely no point in having huge (50g or 100gm/litre) amounts of Sodium Sulphite in part A of this two-part developer. All it will do is to start dissolving the silver halide crystals before any development has begun, and the silver dissolved out will then not be available to act as a physical developer in part B. The result, as Frederick has already seen, is a drastic and pointless loss of film speed, which doesn't reap any benefit in reduced grain clumping. The Sulphite should be almost entirely in part B of the developer, if it's to perform its intended purpose of reducing grain size. A small quantity should remain in part A (I suggest 10 to 15 gm/litre), but only as a preservative for the developing agents.
(posted 8340 days ago)

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