the printmaking technique that uses acid to cut the lines of the image is called
Printmaking A technique used in Intaglio etchings. Like etching, aquatint technique involves the application of acid to make marks in a metal plate. Where the etching technique uses a needle to make lines that retain ink, aquatint relies on powdered rosin which is acid resistant in the ground to create a tonal effect. The rosin is applied in a light dusting by a fan booth, the rosin is then cooked until set on the plate. At this time the rosin can be burnished or scratched out to affect its tonal qualities. The tonal variation is controlled by the level of acid exposure over large areas, and thus the image is shaped by large sections at a time.
Sodium thiosulfate This application as a photographic fixer was discovered by John Herschel. It is used for both film and photographic paper processing; the sodium thiosulfate is known as a photographic fixer, and is often referred to as 'hypo', from the original chemical name, hyposulphite of soda.[12]