Gum printing

Gum printing is also a contact printing process. A pigment is dissolved in gum arabic, this solution is made light sensitive by means of potassium dichromate. After exposion to UV light the print is then developed in a tray of tap water. Often more than one negative is used to provide detail in all tonal ranges. With different negatives for differet colours three colour prints can be made. Using multiple exposures requires very careful registration, which is quite difficult because of shrinkage of the paper. It is a time consuming as well as an addictive process. No two prints of the same negative (s) will be exactly the same.