Photogravure pigment paper
Photogravure is the only form of photo-etching that uses a continues tone film positive. The positive is exposed onto a lightsensitive film of gelatin. This gelatin is called "carbon tissue" or "pigment paper" and is made light-sensitive using a photosensitizing solution. The photosensitizing solution is made with distilled water and any of the following: ammonium bichromate, ammonium dichromate, potassium bichromate or potassium dichtomate. All four are interchangeable. They are also all equally harmful. Wear gloves, goggles and a dusk mask when handling the powder. Click on the following links, for more information about Photogravure: |