'Lilacs, Grey Weather' was created in c.1873 by Claude Monet in Impressionism style. It is kept in the Musée d'Orsay in Paris.
In Lilacs, Grey Weather, Monet used muted colors for the characters, merging them into the background. Where are the legs of the man leaning on the right ? The only thing that catches the eye is the white dress of a woman.
Then, a closer look enables to distinguish the three people thanks to the black and white contrast.
The process is different in Lilacs in the Sun. Spots of light play on the dresses of the two models. Monet applied this effect in several paintings (The Luncheon, Women in a Garden, the Reader...).