8 magg 1873 anni - Photogravure is a photographic technique used with aquatint. The metal plate is heated and dusted with a fine rosin for an aquatint ground. In a darkroom, the image is exposed from a photo positive transparency onto a sensitised gravure carbon tissue or film. This image, in turn, is transferred to the metal plate.
Aggiunto al nastro di tempo:
Data:
8 magg 1873 anni
Adesso
~ 152 years ago