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16 Lessons in Color Theory

Lesson #12

I know that these lessons are coming fast and furious right now, but I have so many requests to do other series and I need to finish this one in the month of March. Hope you can just print these off and work on them when you can.



Nothing is new under the sun. This saying was probably old when King Solomon uttered it. Prehistoric man was ingenious enough to utilize the natural bumps on his cave walls when he painted the massive, roundish bodies of animals - bison, mammoth, boar, and so forth - right over the bumps, thus giving them a three dimensional aspect. Human and animal figures in the surprisingly varied and realistic murals of the Cretan civilization were executed in the form of plaster reliefs, then painted in bright, unshaded colors. The relief created its own shadows when the light hit those murals from one side or another.

In the Early Christian era, halos, crowns, crosses, gold ornaments on holy and royal or imperial personages, were often carved into the wood panel on which the painting was done. Such three dimensional decorations were covered with gold leaf, while the rest of the picture was painted very smoothly. The painting technique remained very smooth, both in tempera and in oils, all through the subsequent periods. Still, it isn't unusual to find a thicker application of paint, where it serves a functional purpose. Rembrandt's Man in a Golden Helmet is a beautiful example, showing repousse work on armor done with thicker paint.

In modern times, impasto, a heavy application of paint, has become a widely accepted technique. Some artists make their impasto so thick that it looks like a veritable bas-relief. Until recently, impasto was possible only in oil painting, since linseed oil dries very slowly and retains its adhesive power forever. The binders in watercolor, gouache, tempera, and casein, on the other hand, cause the respective paints to adhere to one surface in thin layers only. If you apply such colors in heavy piles, they'll soon crack and fall off. Polymer, although applied with water, is an exception. The plastic binders allow you to heap paint upon paint, without the danger of peeling off.


The desire for impasto has grown so remarkably that new materials have been introduced which make it possible to achieve impasto effects in any painting medium. Here are a few:

Underpainting white or texture white: a relatively recent addition to artist's supplies; a quick-drying substance, available for water media as well as for oil painting. You can use it as white paint, mixing it with any color, and develop all kinds of forms and textural effects. Or you can execute the entire work by applying the underpainting white by itself, all over the support. You can have thorns sticking out of your painting, if you wish! Create figures, flowers, trees, rocks, and anything else. Wait until the underpainting dries - a couple of hours in an oil underpainting white, but much faster if you work with polymer - then paint over it as if you were working on the regular support.

Underpainting white mixed with other oil colors, makes the colors dry much faster, so you can quickly build up a picture to any thickness. Build up gradually, however, not in one big heap in order to give each layer a chance to dry a little.

In all cases, read the directions on the label or on the sheet normally given with such whites. Don't take it for granted that you know how to work with any material with which you are not familiar.

Modeling paste or extender: a great substance introduced by manufacturers of polymer, It's even better than underpainting white, because it dries faster, remains flexible, and takes any medium. You cannot work on an underpainting oil white with anything but oil colors. The polymer modeling paste - or extender - is good for watercolor, casein, tempera, gouache, oil, and, naturally, polymer. I recommend the polymer modeling paste or extender very highly.

Gel: another medium to help you in impasto is gel, a vaseline-like substance known to artists for several generations, but now prepared in a scientific manner, so that it won't darken or crack. It used to be good for oil painting only; now it may be mixed with water media as well.

Gel may be applied whenever thickness is required. It adds volume and transparency to any color, without diminishing its intensity. Mix orange with three times its volume in gel, and it will still be as bright as it came from the tube or jar.

There is a gel made for polymer. This may be applied to any part of you painting where thick paint would look right. Pile it on with your painting knife, an old brush, or even chopsticks, if you wish. Let it dry, then paint it. You'll also find that polymer gel absorbs any color upon which it is spread, within a few hours, so that you needn't even paint it, if it absorbs the color that you want.

Which one should you use: underpainting white, modeling paste, or gel? The answer is simple: try em' all, and see which one suits your style, subject, and personality or temperament best. Textural effects are not merely fashionable. They are really pleasing, interesting, occasionally staggering. At any rate, you ought to integrate your textural effects with the subject. Don't employ impasto just to show people that you can do it. Use it where and when it helps you esthetically and technically.


Practically everyone knows how to obtain secondary colors by mixing two primaries. Mixing these SEEMS to be a waste of time, since even the small, introductory sets of colors - in any medium - contain them.


Artists and art students, however, know that there are countless colors and shades in the world around us and in the private world of an artist's imagination. They also know that a forest is not all the same green, that the earth is not the same brown all over, that there is no single color for depicting lakes, seas, rivers in all kinds of weather. they also realize that colors change visually, according to distance, atmospheric conditions, the endless play of light-and-shadow.

It is also obvious that no manufacturer could produce the innumerable hues artists need. And if one did, where could we keep so many thousands of tubes, jars, pans, or cakes of paint? How could we place them on our palettes? This is why color mixing is necessary, and this is why we cannot work with more than a comparatively small number of well selected basic colors.

Even though techniques differ according to media, the general principle of color mixing is the same in all media, with one main exception: transparent watercolors. Transparent watercolors are made lighter by diluting darker hues with the right amount of water. The more water and the less paint, the lighter the shade. You can also purchase lighter shades of the required colors. this procedure is better than adding a lot of water to a darker shade, because a ready-made light hue has greater brilliance than a color which is mostly water. In all other media, colors can be made lighter by adding lighter hues or white.

Most paintings have so many colors that art students at first wonder if it's really possible to mix all those hues from the recommended fourteen or fifteen colors. at the same time, almost without a single exception, students think of colors as what their names imply. They believe that orange is for painting oranges; yellow is for painting lemons, grapefruit, or a canary; blue is the color of sky and calm water. Before starting to paint figures from life, many students go to an art supply store and ask for "flesh color." What flesh color? Why, the color of flesh!


It takes time for students to discover that members of the same race have a large variety of skin colors. As a matter of fact, each individual body varies in color; upper arms, lower legs, thighs, stomach, chest, cheeks, temples, hands, feet are all slightly, or not so slightly, different in hue. Then there are the shadows and highlights, which depend upon the light and the surroundings, too. In an abstraction, you may change any, or all of the colors according to your taste. Still, you must know what you are doing, and how best to achieve the planned, or envisioned effect with the help of color as well as design.

Art students frequently make the mistake of mixing a big batch of colors for the background, for a piece of drapery, for a table, or for whatever large surfaces they intend to paint. "Isn't this a good match?" asks the student. The color does in fact match the object's so-called local color - the color it has by nature, or the color given it in the factory - but it doesn't look like the real thing. The difference between the dye used in coloring the material, and the material's actual appearance in space is tremendous. we know it has a certain color, let's say dusty green, but that dusty green looks brighter, more yellowish in the upper left corner, than in the upper right; it looks bluish in the lower left and reddish in the lower right, depending on illumination and on nearby objects reflected in it.

Watch a wall on a day when the sun plays hide-and-seek behind clouds. The wall looks brighter, warmer when the sun is out; it turns gray, cool when the sun is hidden. The very common idea of painting a whole background one solid color, then adding the objects on top of it, is a major mistake among beginners. At best it offers a POSTER effect, with pleasing flat colors.

You have to learn to observe. Look, look, and look again. Look with your eyes, not with your preconceived notions. Everything is right in front of you; there is no mystery attached to seeing colors. Gradually, you'll realize that colors are meaningless by themselves; they must be correlated with other colors around them. You can hit one single note on the piano and know what note you hit, but it's merely a sound, an accidental sound. You have to surround the note with others, so to speak, before you obtain what can be called music. The same relationship exists between colors and art, as between notes and music.


Few colors in nature are visually pure. In all likelihood, you'll find a color slightly bluish, reddish, or yellowish. Pure colors are normally used in posters only, or in dyeing textiles.

Let's say you need a very dark red. Take the darkest you have - alizarin crimson - add a little blue, green, or black, or a drop of each. By "little" I mean that all you do is touch green, blue, or black with the corner of your brush, and mix it into the alizarin. Add more, if necessary. ( I advise you to look every time you do anything in art, and ask yourself if you are doing the right thing.)

Suppose you want to obtain a lighter red. Is it to be brilliant or mellow, warm or cool, pinkish or yellowish? Don't just add white to make it lighter. White turns alizarin crimson into pink, a rose color, while it makes peach out of cadmium red. You may have to combine alizarin, cadmium red, orange, and yellow for a warm red of high intensity. By adding white, instead of yellow, you'll have an equally light and bright, but cooler red. Whatever you mix, test every brush stroke before adding more paint.

To mix or modify any light shade, begin with the lightest hue close to it. For a pale green, take white and add a touch of phthalo green. If it isn't the right shade, add a pinpoint of cobalt, phthalo blue, or ultramarine blue, whichever gives you the desired effect; if it isn't bright enough, dip a corner of your brush in light yellow, and stir it into the green. Colors are stronger in some brands than in others, and artists don't work like pharmacists, weighing each ingredient on a scientific scale according to a prescription. Mix the colors on your palette, but the final proof is in the painting. Look at each color as you place it next to, or on top of, other colors.

It's possible to mix a pint can of household paint with half a can of another color, but this isn't the way in fine arts.

You aren't preparing a pale of paint for painting your kitchen, where you must be sure to have plenty of paint, thoroughly mixed in order to prevent dirty streaks. In fine arts, you can always change a mixture if it isn't just right. The wrong color won't kill the painting the way an incorrectly filled prescription might kill the patient. One of the beautiful features of working in color, in any medium, is to experiment, to watch the results, to see how the smallest bit of another color can help or harm your painting.


Here's the most practical and sensible method of finding out what color mixing really means: take a six or eight inch wide strip of canvas, paper, or whatever support you like, and paint an inch of every color you have. Go from top to bottom, leaving about an inch of space between colors. Rub a small amount of white into each color, but leave about one-third of each stripe intact. Compare the mixtures with the original hues. As I've already said, alizarin crimson becomes pink; cadmium red turns into peach when the white is added; you have to add a great deal of white to cadmium yellow before you can notice the difference; white creates entirely different shades out of every blue. The same varied effects occur when white is mixed into any green, yellow ocher, burnt sienna, cobalt violet, or any other color you may have. Rub an additional amount of white into each color, and you'll see further interesting variations.

Now mix every basic color with all the other colors. For instance, add cadmium yellow light to all your colors; cobalt blue to all your colors; phthalo green to all your colors; and so forth. A vast array of colors and shades is at your disposal, opening up a vista of a sumptuous world of color. After some experience, you'll be able to obtain every imaginable shade of every perceivable color.


Making colors darker also has a pitfall. Your first idea may be to add black. Although red, blue, green, and brown can be made darker by adding a little black, try to add another dark hue: ultramarine blue to red or green, alizarin crimson to blue.

Even if you do add black, it's usually better to mix it with a drop of some other dark hue too. Yellow can be made darker by mixing it with yellow ocher, but it will no longer be really yellow. Black turns yellow into a dirty green. Ocher can be deepened with burnt sienna and a bit of black.


Brought up on the tradition (or superstition) that black is not a color, but a lack of all color, many artists work without it. Nobody recommends the use of plain black over large sections of your painting; not even Goya's famed "black paintings" in the Prado Museum in Madrid are jet black.

Add a little red, blue, or green to make your black warmer, or cooler, and to take away that flat, papery appearance it has when applied to a large spot. A black dress is not truly black all over; it has lights, shadows, and reflections that break it into many different shades.

Too much white in any color makes it what we call "chalky," a fully descriptive expression, because such colors do appear to have been smeared with white chalk.

Too much reddish blue in a dark color will cause an "inky" impression, as if you had spilled ink on your painting. Such a spot appears to be a big hole in your picture, something that doesn't belong there. Watch out for such exaggerations.

Look for the next few lessons to come together rather quickly. Next will be color effects. See you soon.