Video 1: Calotype Paper Photographic Process

William Henry Fox Talbot invented the calotype, the first practical negative-positive photographic process. It was patented by him in 1841.

The concept of negative-positive photography, allowing the production of an unlimited number of prints from a single negative, has formed the basis of photographic practice up until the last few years.

• A sheet of paper is treated with light-sensitive silver compounds before exposure in the camera.
• The image is then developed in gallo-nitrate of silver and fixed.

Demonstration by Michael Gray (YouTube video. No sound track).

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