Christine Garceau Fine Art

Cyanotype photography refers to the process of contact printing a picture by using sunlight and a series of chemicals without a camera. The chemicals involved in cyanotype photography include Prussian blue, aqueous potassium ferricyanide and aqueous ferric ammonium citrate. When producing a cyanotype picture, the paper (or other printing medium) is treated with each of the chemicals.

The image is then placed upon light treated paper, weighed down with glass and taken out into the sun. The combination of sunlight and chemicals will then imprint the image onto the paper in a dark blue or gray color. Keep the paper in the sun for no more than five minutes depending on the intensity of light, or until the paper is visible bluish-grey.

When the paper has turned, remove the glass and rinse the chemicals off the paper with water. After the paper is dry, the print is complete.

Objects used in cyanotype photography should be flat and opaque. When using the cyanotype method, remember that the prints turn out best with greater contrast between objects.

The cyanotype process was developed by Sir John Herschel in the early 1840's In the 1870's the process was used for making blueprints and commercial paper became available for marketing to engineers, architects and draftsmen to copy drawings because it resulted in a chemically stable, permanent print. Blueprints are still made today by this technique because it is less expensive than newer technologies. However, as the prices for digital technologies come down, we may see cyanotype blueprints disappear along with the typewriter and stereoscope.