Photography

Alternative process

In photography, an alternative process is any chemical process that is considered primarily historical. Because of how dominant the silver gelatin process has become, "alternative" is largely understood as processes other than silver gelatin film or photo paper. Examples include processes still based on silver salts—like collodion processes or salt prints—as well as completely alien chemistries based on iron salts—like the cyanotype or platinum print—or dichromate salts—gum and carbon printing. Silver gelatin is preferred in large part for its relatively high sensitivity to light. Although some alternative processes like the Daguerreotype or the calotype require just a little more lighting, or a longer exposure to form an image, many other processes are unable to form images quickly enough with visible light to be useful for photography, and are instead used as printing processes. These processes may require either a silver gelatin negative or a "digital negative" (a transparency printed on a digital printer) to be used to make contact prints from.

Also on this shelf

See also

• ▸Hilda Geissmann
• ▸Creighton Mine
• ▸Hamilton Biscoe Hillyer

Uncatalogued shelf

Text from Wikipedia; plate via Wikimedia Commons. Text CC BY-SA 4.0; plate freely licensed (see Commons). Source record. Images and catalogue data are reproduced from open-access collections.