A cyanotype print with the fern that cast the shadow seen in the print. In this process an object is placed on the ultraviolet sensitive chemically treated paper and exposed to a strong UV light source in this case sunlight. The object is then removed and the print washed in cool water to remove the unreacted chemicals. Cyanotype is a photographic printing process that produces a cyan-blue print. Engineers used the process well into the 20th century as a simple and low-cost process to produce copies of drawings,referred to as blueprints. The process uses two chemicals: ammonium iron(III) citrate and potassium ferricyanide. The English scientist and astronomer Sir John Herschel discovered the procedure in 1842 | |
Licence : | Droits gérés |
Crédit: | Science Photo Library / Kinsman, Ted |
Taille de l’image : | 5110 px × 3744 px |
Model Release : | Non requis |
Property Release : | Non requis |
Restrictions : |
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