"Yellow and Purple."—It is this principle which is the cause of the peculiarity in the technique of certain "Impressionist" painters. The "yellow lights and purple shadows" is only placing by the side of a color that color which will be most effective in forcing its note.
Brilliancy is what these men are after, and they get it by the study of the law of color contrast and color juxtaposition. The effect of complementaries in color contrast is what you must study for this, for the theory of it. For the practice of it, study carefully and faithfully the actual colors in nature, and try to see what are the real notes, what the really component colors, of any color contrast or light contrast which you see. Purple shadows and yellow light re-enforcing each other you will find to exist constantly in nature. Refine your color perception, and you will be able to get the result without the obviousness of the means which has brought down the condemnation on it. Closer study of the relations is the way to find the art of concealing art.
But yellow and purple are not the only complementaries. All through the range of color, the secondaries and tertiaries as well as the primaries, this principle of complement plays a part. There is no color effect you can use in painting which does not have to do, more or less, with the placing of the complementary color in mass, to emphasize; or mixed through to neutralize, the force of it. Train your eyes to see what the color is which makes the effect. Analyze it, see the parts in the thing, so that you may get the thing in the same way, if you would get it of the same force as in nature.
Practical Color.—All these theoretical ideas as to color have their relation to the actual handling of pigment, which is the craft of the painter. The facts of contrasting and harmonizing color relation have a practical bearing on the painter's work, both in what he is to express and how he is to do it; as to his conception of a picture and his representation of facts. In his conception he must deal with the possibilities of effect of color on color. The power of one color to strengthen the personal hue of another, or its power to modify that hue, is a fact bearing on whether the color in the picture is the true image of the color he has seen in his mind. In the same degree must this possibility affect his representation of actual objects.
The greatest possibilities of luminosity in sunlight or atmospheric effects come from the power to produce vibration by cool contrasted with warm color. You will find that a red is not so rich in any position as when you place its complementary near it. At times you will find it impossible to get the snap and sparkle to a scarlet—cannot make it carry, cannot make it felt in your picture as you want it without placing a touch of purple, perhaps, just beside it; to place near by a darker note will not have the same effect. It is the contrast of color vibration, not the contrast of light and shade, which gives the life. And at the same time that you enhance the brilliancy of the several notes of color in the picture, you harmonize the whole. For the mosaic of color spots all over the canvas brings about the balance of color in the composition, and harmony is the result.
Study Relations.—You must constantly study the actual relations of color in nature. You will find, if you look for it, that always, just where in art you would need a touch of the complementary for strength or for harmony, nature has put it there. She does it so subtly that only a close observer would suspect it. But the thing is there, and it is your business to be the close observer who sees it, both for your training as a colorist, and your use as an interpreter of nature's beauties. It is your business to see subtly, for nature uses colors subtly. The note sparkles in nature, but you do not notice the complementary color near it. Can you not also place the complementary color so that it is not seen, but its influence on the important color is felt? It is by searching out these finesses of nature that you train your eye. You must actually see these colors. At first you may only know that they must be there because the effect is there. But your eye is capable of actually recognizing them themselves, and you are no painter till it can. The theoretical knowledge is and should be a help to you, but the actual power of sight is most important. A painter may use theoretical knowledge to help his self-training, but power of eye he must have as the result of that training. The instantaneous recognition of facts and relations, the immediate and perfect union of eye and thought, are what make that intuitive perception which is the true feeling of the artist.
Work this out with eye and palette. Study the color and its relation in nature, and study its analogy in the pigment touches on the canvas.
The Palette.—You try to attain nature's effects of light with pigment. Pigment is less pure than light. You cannot have the same scale, the same range, but you must do the best you can, and the arrangement of your palette will help you. As you have not a perfect blue, a perfect red, and a perfect yellow, you must have two colors for one. Your paints will always be more or less impurely primary. No one red will make a pure purple with blue, and an equally pure orange with yellow. Yet pure purple and pure orange you must be able to make. Have, then, both a yellowish or orange red and a bluish or purplish red on your palette. Do the same with blue and yellow. In this way you can not only get approximately pure secondaries when you need them, but the primaries themselves lean somewhat towards the secondaries, so that you can make very delicate combinations with pure colors. A bluish yellow and a yellowish blue, for instance, will make a rather positive green. By using a reddish yellow and a bluish or purplish red, you practically bring in the red note, and make a grayer green while still using only two pigments.
So, too, you get similar control of effects by the use of opaque or transparent pigments, the transparent ones tending to richness, the opaque to dulness of color. Various processes in the manner of laying on paint bring about these different qualities, and will be spoken of in the chapter on "Processes."
Classify your pigments in your mind in accordance with these characteristics. Think of the ochres, for instance, as mainly opaque, and as yellows tending to the reddish. With any blue they make gray greens because of the latter quality, and they make gray oranges with red because of the dulness of their opacity and body. For richer greens think of the lighter chromes and cadmium yellows or citrons; and for the richer oranges, the deeper cadmiums and chromes. With reds, work the same way, scarlet or orange vermilions for one side of the scale, and the Chinese or bluish vermilion on the other side. The deeper and heavier reds fall in line the same way. Indian red is bluish, light red and Venetian red are yellowish.