Colour and light

Detail of illustration from M. E. Chevreul, 'Principles of Harmony and Contrast of Colours', 1860
Detail of brushstrokes
Impressionist artists wanted to replicate the colours of the natural world. They noticed that shadows are not simply black, and that clouds are not simply white, but made up of a multitude of colours. The artists were interested in colour theory, and in particular, the research of Michel-Eugène Chevreul, whose colour wheel (1839) helped to illustrate the concept of complementary colours. For example, when orange and blue are placed beside each other, like in this detail from Monet's painting, the intensity and hue of each colour is enhanced. This gave rise to theories about the optical combination of colours that was important for Impressionist techniques and especially for Neo-Impressionist painters.

Detail from Claude-Oscar Monet (1840–1926), Argenteuil Basin with a Single Sailboat, 1874
Detail from Claude-Oscar Monet (1840–1926), Argenteuil Basin with a Single Sailboat, 1874
Notice how the shadows in Monet’s painting, Argenteuil Basin with a Single Sailboat, are made up of dabs of purple and red paint and how the sky includes both pink and blue.  Light, and its effects on various surfaces, was a major interest for most Impressionist artists, but particularly for Monet. They recognised that natural light is constantly changing and that this affects the colour and form of the landscape. They wanted to convey how sunlight reflects off surfaces in varied ways, according to the times of the day, weather conditions, and seasons. In this painting Monet used different brushstrokes to express how each surface reacts to light - the shimmering water, the soft clouds, the stiff tree branches, and the crisp autumnal leaves.