Gumoil Photographic Prints: A Modern Alternative Process

Gumoil is the polychromatic, photographic print-making process, based on black and white still film created by photographer, Karl P. Koenig. It is conceptually related to several methods of the 19th Century. Gumoil prints often have the atmospheric values of photography's early days. The process can best be understood as the inverse of the historic gum bichromate print method. But, unlike that method, gumoils are printed from a black and white positive transparency enlarged from a smaller black and white negative. This big positive image is then contact printed on 100% cotton paper which has been coated with light sensitive, unpigmented, gum arabic. Developed in plain water and dried, this becomes a latent or negative-appearing print with white spaces which will darken, like the original image's shadow areas when the print is rubbed vigorously with oilpaint. The light-hardened gum portion of the paper's surface corresponds to the white spaces and resists the oil color. Subsequent tones are added by etching residual gum with bleach baths, washing, and rubbing in other, lighter, oil colors. Each print is unique and takes two to four weeks to complete.

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