The Painter in Oil / A complete treatise on the principles and technique necessary to the painting of pictures in oil colors

by Daniel Burleigh Parkhurst

Diffused Light.—Much of the characteristic quality of out-door light is the result of the diffusion of light due to both the refraction and the reflection of the sky. The light which bathes the landscape comes in all directions from the sky. Necessarily, then, the sky will be in most cases far higher in value than anything under it. Even the blue of the sky, which looks darker than some bit of light in the landscape, you will find, if you can manage to get them to tell against each other, will be the more luminous of the two, and will look lighter. There are times when the sun glares on a white building or a piece of white sand, when the white tells light against the blue. But these are exceptions, and if we could get a blue paint which would give the intensity of color, and also the brilliancy of the light, even these cases would be most truly represented with the sky as the higher value. It is a case of whether to sacrifice value to color, or the reverse, as we cannot have both.

Sometimes, however, in a storm, the dense dark of the storm sky is really lower in value than some white object against it, especially if there be a bit of sun breaking through on it.

But in general, nevertheless, you should consider the sky as always lighter and more luminous than anything under it.

Three Planes.—It will help you in understanding the way the light falls on landscape to consider everything as in one of three planes, and these planes taking greater or less proportions of light according to the position of the sun with reference to them.

The position of the sun changes from a point immediately over, to a point practically at right angles to all objects in nature. Everything that can exist under the sun will come in one of these planes, and at some time in the day in each. The vertical, the horizontal, or some sort of an oblique between these two. If the sun is overhead exactly, the flat ground, the tops of trees and houses, will get the full amount of sunlight. The vertical planes, sides of houses, depths of foliage, etc., will get the least, some of them being lighted only by diffused and reflected light. The planes lying between these two extremes will get more or less, according as they are more or less at right angles to the direct rays of the sun. And as the sun declines from the zenith, the vertical planes get more and more and the horizontal planes less and less of the light, till in the late afternoon the banks of trees and sides of buildings and cloud-masses are gilded with light, and the broad horizontal plains of land and water are in shadow.

However obscured the sun may be, this principle holds more or less; and it makes clear and helps you to observe and notice many facts in landscape light and shade which it is necessary to know.

Millet said that all the beauty of color and value, and the whole art of painting, rested on the comprehension and observance of these facts.

He said that as the planes of any form turned towards or away from the light and so got more or less of it, and as one form stood more or less far back of another and the atmosphere came between, the color and value changed; and in the observance of this, and its representation as applied to any and every object or group of objects, lay the whole of painting. All the possible beauties of the art rested on it. He showed a painting of a single pear in which these things were most subtly observed, and said that that painting was as complete and perfect as any painting he could do simply because in the observance of these relations was implied the observance of everything which was vital to painting.

Short Sittings.—This characteristic, and the steady change of position of the sun and its effects on all the objects which are directly lighted by it, make it necessary, whenever you are painting from nature out-of-doors, that you should not paint at one thing very long at a time. The light changes pretty rapidly; at high noon it only takes a few moments to exactly reverse the light. It is seldom that you can do any just study for more than an hour or an hour and a half at a sitting. Some men do work two or three hours, but they are not studying justly all that time; for that which was light is dark three hours later, and any true study of value and color is impossible under these conditions. Of course on gray days this is less marked, but you must suit your sittings to the time and facts.

It would be better if you had more canvases, and worked a short time on each, and many days on all. You would have the truest work.