Unidentified Photographer, Feeding the Squirrels, ca. 1908
Unidentified Photographer, [Interior], ca. 1908
Unidentified Photographer, [Unidentified Girl], ca. 1908
Unidentified Photographer, [Boat], ca. 1906
Unidentified Photographer, [Boat (verso)], ca. 1906
The cyanotype process was introduced by Sir John W.F. Herschel in 1842. The cyanotype image is created by the reaction of ammonium iron citrate and potassium ferricyanide under UV light. The result forms a brilliant, lush Prussian blue, which was also the first synthetic pigment.
Cyanotypes were first put to photographic use by botanist Anna Atkins to create plant illustrations and engineers to create blueprints. It is extremely permanent, and therefore favored by artists concerned with the preservation of their images. Other notable photographers who utilized the cyanotype process were Eadweard Muybridge, Henri Le Secq, and Edward Curtis. The simple-to-use process was also well received by amateurs to create images, like these postcards printed in the first decade of the 1900s.