The photogravure process is one of the oldest photomechanical printing processes, dating back to William Henry Fox Talbot (1800-1877) who patented his technique in 1852. In Talbot’s method, a copper plate was coated with a chemical mixture of sensitized gelatin which reacts when exposed to sunlight. A photographic negative is then etched into the plate using an acid bath, creating an impression on the plate. Finally, the prepared printing plate can then be inked and run through a printing press. In comparison to other photographic processes of the time, multiple prints could be made from one gravure plate, whereas positive prints on metal plates, such as daguerreotypes, were unique and could not be reproduced.
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Image Credit: Guido Rey - The Letter