Realism And Impressionism In France

(via The Outline of Art) William Orpen writes:

The nineteenth was a scientific century during which great additions were made to our knowledge of optics. The French scientist Chevreuil wrote a learned book on color, which was studied with avidity by the younger painters. It became clear to them that color was not a simple but a very complex matter. For example, we say that grass is green, and the green is the local color of grass, that is to say, the color of grass at close range, when we look down on it at our feet. But grass-covered hills seen at a great distance do not appear green, but blue. The green of their local color is affected by the veil of atmosphere through which we view it in the distance, and the blue we see is an example of atmospheric color. Again, the local color of snow is white, but everybody who has been to Switzerland is familiar with the ‘Alpine glow’ when the snow-clad peaks of the mountains appear a bright copper color owing to the rays of the setting sun. This ‘Alpine glow’ is an example of illumination color, and since the color of sunlight is changing throughout the day, everything in Nature is affected by the color of the light which falls upon it.

The landscape painter, then, who, wishes to reproduce the actual hues of Nature, has to consider not only ‘local color’ but also ‘atmospheric color’ and ‘illumination color’, and further take into consideration ‘complementary colors.’ One of the most important discoveries made by the later Impressionist painters was that in the shadows there always appears the complementary color of the light. We should ponder on all these things if we wish to realize the full significance of Manet’s saying, ‘The principal person in a picture is the light.’

This new intensive study of color brought about a new palette and a new technique. For centuries all painting had been based on three primary colors, red, blue, and yellow; but science now taught the painters that though these might be primary colors in pigment, they were not primary colors in light. The spectroscope and the new science of spectrum-analysis made them familiar with the fact that white light is composed of all colors of the rainbow, which is the spectrum of sunlight. They learnt that the primary colors of light were green, orange-red, and blue-violet, and that yellow—though a primary in paint—was a secondary in light, because a yellow light can be produced by blending a green light with an orange-red light. On the other hand green, a secondary in paint because it can be produced by mixing yellow with blue pigment, is a primary in light. These discoveries revolutionized their ideas about color, and the Impressionist painters concluded they could only hope to paint the true color of sunlight by employing pigments which matched the colors of which sunlight was composed, that is to say, the tints of the rainbow. They discarded black altogether, for, modified by atmosphere and light, they held that a true black did not exist in Nature: the darkest color was indigo, dark green, or a deep violet. They would not use a brown, but set their palettes with indigo, blue green, yellow, orange, red, and violet, the nearest colors they could obtain to the seven of the solar spectrum.

Further, they used these colors with as little mixing as possible. Every amateur in watercolor knows that the more he mixes his paints, the more they lose in brilliancy. The same is true of oil paints. The Impressionists refrained, therefore, as much as possible from mixing colors on their palettes, and applied them pure in minute touches to the canvas. If they wanted to render secondary or tertiary colors, instead of mixing two or three pigments on the palette, they would secure the desired effect by juxtaposed touches of pure colors which, at a certain distance, fused in the eye of the beholder and produced the effect of the tint desired. This device is known as optical mixture, because the mixing is done in the spectator’s eye. Thus, whereas red and green pigment mixed on a palette will give a dull grey, the Impressionists produced a brilliant luminous grey by speckling a sky, say, with little points of yellow and mauve which at a distance gave the effect of a pearly grey. Similarly the effect of a brilliant brown was given by the juxtaposition of a series of minute touches of green, red and yellow; and this association of minute touches of three pure colors set up a quivering vibration which had greater luminosity than any streak of brown pigment. It was an endeavor to use paints as if they were colored lights.

Realism And Impressionism In France (continued)