Portret van een onbekende vrouw met lang haar en een tule before 1890

This photograph of an unknown woman with long hair and a tulle was made by Robert Demachy. The photograph's distinctive reddish-brown tone is the direct result of Demachy's use of the gum bichromate process, which allowed for greater manipulation of the image. In this technique, a coating of gum arabic, pigment, and a light-sensitive chemical is applied to paper. Upon exposure to light through a negative, the coating hardens, allowing the artist to wash away the unexposed areas. Demachy used the camera as a starting point, but the real work began in the darkroom. Gum bichromate was an early form of alternative photography that embraced the handmade. It allowed photographers like Demachy to emulate the look of paintings or drawings, softening details, adding textures, and creating atmospheric effects. The labor-intensive process gave the artist full control, blurring the lines between photography and the fine arts. This approach asserted photography as a legitimate artistic medium in its own right.