FORMULARY D-25 FINE GRAIN FILM DEVELOPER is a fine-grain film developer that contains metol and a mild silver solvent, sodium metabisulfite. The grain obtained with D-25 resembles that obtained with Developer 12, however, D-25 contains metol rather than the toxic p-phenylenediamine found in Developer 12. Contrast is normal with D-25, but softness may result. D-25 is reputed to be a non-staining developer, however, staining and dichroic fog have been reported with modern fine-grain films. Therefore, the developer should be tested with your current film before this developer is used extensively. The chemicals in this kit are used to prepare a working solution that has a shelf life of two months. A liter of working solution is used to process 4 rolls of film. The capacity is extended to 25 rolls per liter by using the replenisher, Formulary DK-25R.