Meaning of self-toning in English:

self-toning

Pronunciation /ˌsɛlfˈtəʊnɪŋ/

adjective

historical Photography
  • Designating photographic paper in which the emulsion contains a chemical substance that allows the image to be toned during fixing, rather than in a separate process.

Origin

Late 19th century; earliest use found in Photographer's World.