Effets de soir (also called effets de soir et de matin)[1] are the effects of light caused by the sunset, twilight, or darkness of the early evening or matins.
They appear frequently in works by such painters as Vincent van Gogh,[2] Bernhard Fries,[1] Armand Guillaumin,[3] and Camille Corot.
[4][5] Literally, it means "effects of evening" in French.
This was part of a group of techniques used by Impressionists such as impasto, en plein air, color theory, and thick strokes of oil paint on canvas.
In 2008, the Museum of Modern Art curated a major exhibit of van Gogh's work of effets de soir.