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Pyrogallol developer with a very small tendency for staining.

Solution A
Potassium metabisulphite15grams
Sodium sulphite60grams
Water to make1liter
Solution B
Sodium carbonate monohydrate75grams
Water to make
Mix chemicals in order.

To make Solution A, the sodium sulphite and sodium metabisulphite should be put into hot water at the same time and the solution brought to a boil. Boil for a minute or two, cool and dissolve the pyrogallol. The boiling increase the life of the solution and prevents staining.

To use, dilute 1:1:2 and develop in a tray for 4–6 minutes at 18.5°C. For a stronger negative, dilute 1:1:1 or omit water entirely.

As a rule, contrast and density may be increased by decreasing the recommended amount of water to dilute the stock solution by 50%–66%. Softer negatives can be obtained by using 50%–100% more water than is specified for normal results.