Cyanotypes
Cyanotype is a photographic printing process that produces a cyan blue print, thus the name. Engineers used the method well into the 20th century as a simple and low-cost means to produce copies of drawings, referred to as blueprints. The process uses two chemicals: ferric ammonium citrate and potassium ferricyanide.
The English scientist and astronomer Sir John Herschel discovered the procedure in 1842, years before the discovery of traditional photographic processes. Although Herschel invented the technique, Anna Atkins is sometimes considered the first female photographer because she created a series of cyanotype limited edition books that documented ferns and other plant life from her extensive seaweed collection. She placed the specimens directly onto coated paper and allowed the action of sunlight to create a silhouette effect.
The English scientist and astronomer Sir John Herschel discovered the procedure in 1842, years before the discovery of traditional photographic processes. Although Herschel invented the technique, Anna Atkins is sometimes considered the first female photographer because she created a series of cyanotype limited edition books that documented ferns and other plant life from her extensive seaweed collection. She placed the specimens directly onto coated paper and allowed the action of sunlight to create a silhouette effect.