Response to adding sodium sulfite to developer

Sodium sulfite added to FG7, 9% reccomended, increases speed of film and REDUCES substantially the development time! I have tested with densitometer film speed and development times for FG7 with and without the Sodium Sulfite. There is at least a 1/3 increase in film speed with SS and a 40% reduction time for development. I am shooting HP5+ developed in 5 reel patterson tank with inverse agitation. My development time for HP5+ with SS is 6 min rated at 400EI; without SS 11and1/2min rated at 320EI. Amazing I think! Sodium Sulfite acts as both a preservative preventing Oxidation and also as a developer; sounds contradictory, but that is what it does! Hello to all you RIT GRADS who remember Materials and Procceses with Prof Stroebel.

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