Most proprietary forms of developer (Xtol, T-Max, etc.) do not have published formulae. They are only sold as ready-mixed concentrated solutions or occasionally as powders. However, the table below gives some well-established developers you can prepare yourself at relatively low cost from their constituent chemicals († = handle with special care).
|Chemical||When formula quotes weight for||And the only available form is||Multiply weight by|
|Sodium carbonate||Anhydrous or desiccated||Monohydrate or H2O||1.2|
|Sodium carbonate||Anhydrous or desiccated||Crystalline or decahydrate (10H2O)||2.7|
|Sodium sulfite||Anhydrous or desiccated||Crystalline/heptahydrate (7H2O)||2|
|Sodium thiosulfate||Crystalline/ pentahydrate ...|