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The world Printings
Photogravure registers a wide variety of tones, through the transfer of etching ink from an etched copperplate to individual dampened paper run through an etching press. The unique tonal range comes from photogravure's variable depth of etch, that is, the shadows are etched many times deeper than the highlights. Unlike half-tone processes which just vary the size of dots, the actual quantity and depth of ink wells are varied in a photogravure plate and are often blended into a smooth tone by the printing process. Photogravure practitioners such as Peter Henry Emerson and others brought the art to a high standard in the late 19th century. The speed and convenience of silver-gelatin photography eventually displaced photogravure which fell into disuse after the Edward S. Curtis gravures in the 1920s. Many years later, photogravure has experienced a revival in the hand of Aperture and Jon Goodman, who studied it in
The very sharp printing obtained from the intaglio process is very hard to imitate by other means. Intaglio also allows for the creation of latent images which are only visible when the document is viewed at a very shallow angle.
The rotogravure process is still used for commercial printing of magazines, postcards, and corrugated (cardboard) product packaging.
In the latter quarter of the 19th century, the method of image photo transfer onto carbon tissue enclosed with light-sensitive gelatin was discovered and was the beginning of rotogravure.
Two main types of printing plate materials: photopolymer and steel. Photopolymer plates are the trendiest, providing a good do-it-yourself option. These are naturally used in short to medium production runs. Steel plates come in two options: thin steel for medium to long runs, and thick steel for very long runs. Both steel plate types are commonly processed by the plate supplier as it involves the use of specialized equipment.