Description
Potassium Ferricyanide is use in Cyanotype printing and iron and copper toning. Also used as an oxidising agent in black-and-white photography with sodium thiosulfate (hypo) to reduce the density of a negative or gelatin silver print (known as Farmer’s reducer). Used to also solve problems from overexposure of the negative and brighten the highlights in the print.This is sold as fine crystals/powder form.
