Sabattier effect

[ sah-buh-tyey, sab-uh- ]
/ ˌsɑ bəˈtyeɪ, ˌsæb ə- /

noun Photography.

the alteration of the image tones of a photographic print by briefly reexposing the negative after it has been partially developed.

Origin of Sabattier effect

1925–30; Sabattier, erroneous for Armand Sabatier (1834–1910), French physician and scientist, who developed the effect