
PURPOSE (concern argentic negatives) : to clear up the blacks of the movie to give of the detail in the clear parts of the image during the edition (use of the mixture ferricianure / hyposulfite / water in basin or at the brush):
Whether it is for the ferricianure of potassium or hyposulphite of soda, to mix a waiting preparation : 1/3 of chemical and the rest of tepid water to facilitate the dilution.
Solution concentrated usually used to clear up the photographic negatives : prepare a compound mixture of: 1 part of waiting preparation of ferricianure + 1 part of waiting preparation of hyposulphite of soda + 5 or 6 times this volume in water.
