Sodium hydrosulfite

Sodium hydrosulfite
Is used as a fogging agent in reversal processing.
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Sodium hydrosulfite - used as a fogging agent in reversal processing.
Sodium hydroxide - highly active alkaline accelerator used in conjunction with hydroquinone to produce high contrast developers.

Sodium dithionite (aka sodium hydrosulfite) is a toxic, white crystalline powder with a weak sulfurous odor. It is stable under most conditions, although it will decompose in hot water and in acid solutions.

See also: Fogging, Acid, Solubility, Fogging agent, Reduction