The Gum Bichromate Book: Non-Silver Methods for Photographic Printmaking

Rating:
Summary: Excellent book on an interesting photo printing technique
Review: I've had this book for quite a few years. It's a really good reference and instructional book on how to do gum bichromate printing for black and white negatives.

Normal photographic printing is done on silver bromide paper; the photosensitive silver crystals make the black of the print. In gum bichromate printing, chromate is used in a gum emulsion mixed with colored pigments to harden under light exposure. (I'm trying to stay away from the chemistry here.) After making a negative to use for contact printing, the negative and coated paper are exposed to light. Where light penetrates your negative, the gum-chromate-pigment mixture hardens and stays on the paper. Where not exposed to light, the solution washes away.

This isn't an easy technique, but is a very lovely one, and even more interesting when mixed with other techniques like cyanotype. It's also possible now to use laser printer to produce some of the contact negatives you need.

The only caveat I must add is that chromium compounds are TOXIC. So if you are not experienced at handling chemicals, this technique is NOT for you and your home darkroom. However, if you have experience in good lab technique and know your way around a darkroom, this is a very alluring technique to make some wonderfully, almost hand-colored looking prints. This fits in especially well with the current interest people have in handmade books and journals.

Rating:
Summary: Excellent book on an interesting photo printing technique
Review: I've had this book for quite a few years. It's a really good reference and instructional book on how to do gum bichromate printing for black and white negatives.

Normal photographic printing is done on silver bromide paper; the photosensitive silver crystals make the black of the print. In gum bichromate printing, chromate is used in a gum emulsion mixed with colored pigments to harden under light exposure. (I'm trying to stay away from the chemistry here.) After making a negative to use for contact printing, the negative and coated paper are exposed to light. Where light penetrates your negative, the gum-chromate-pigment mixture hardens and stays on the paper. Where not exposed to light, the solution washes away.

This isn't an easy technique, but is a very lovely one, and even more interesting when mixed with other techniques like cyanotype. It's also possible now to use laser printer to produce some of the contact negatives you need.

The only caveat I must add is that chromium compounds are TOXIC. So if you are not experienced at handling chemicals, this technique is NOT for you and your home darkroom. However, if you have experience in good lab technique and know your way around a darkroom, this is a very alluring technique to make some wonderfully, almost hand-colored looking prints. This fits in especially well with the current interest people have in handmade books and journals.