Michael Gaines
Photographer. Visual Artist. Educator. Historian.
Gum-Bichromate
Gum Bichromate is a process that tests one's patience, and is not exactly ideal for someone who has little patience. Before you can begin to create the print, you have to make sure that your paper can take the print, which involves soaking your paper in hot water to remove factory sizing, and then soaking the paper in a boiling gelatin/chrome-alum mix to resize the paper. Twice. Once that is done, you apply a single color layer consisting of a mixture of watercolor pigment mixed with gum arabic and dichromate. After exposing your negative, you place the paper on the surface of a water bath to remove any unexposed chemistry and keep alternating fresh baths until the water runs clear. After the paper has dried and been pressed, you repeat the process all over again with your next color.