Saturation refers to the brightness or dullness of colors.

The objectives of this lesson are to:

Learn how color works, why some colors are bright and some are dull.

Learn how to decrease the saturation of a color by mixing it with it's complement.

Make a Saturation scale after mixing an exact set of complementary colors.


  A chromatic gray is a very dull color, but not quite achromatic.    
You have seen the term before as part of achromatic (without color) and monochromatic (with only one color). It really means the amount of color that is reflected which translates into brightness. Another term that also describes this is intensity.

This is review. See color for more information.
Different wavelengths of light appear to be different colors. White light is made up of all the wavelengths of visible light. When it passes through a glass prism it is divided into it's component wavelengths and a spectrum of different colors is made.

When white light hits a surface, a certain amount of it is reflected back. If the surface is white, most of the light is reflected unchanged in color and the surface looks white. If the surface is black, most of the light is absorbed and little is reflected. When the light hits a colored surface, some of the wavelengths of light are absorbed and some are reflected. Absorption is the reason this is called the subtractive or pigment theory of color.
If the surface is green the green wavelengths are reflected and the others are absorbed. If most of the green light is reflected, the surface will look bright green (highly saturated). If only a little of the green light is reflected, the surface will look dull green (low in saturation). Therefore, for a surface (paint) to appear green, it must absorb (subtract) most of the wavelengths of light that are NOT green and reflect those that are.

A light green occurs when some white light is also reflected with the green light. Dark green occurs when very little white light is also reflected with some green light.


When any two colors are mixed together the results are always duller than the "parent" colors. You can diagram this on the color wheel by drawing straight lines, called chords, between the colors mixed. The colors you get from the mixture are along the chord line. The closer the chord comes to the center of the color wheel (neutral) the duller the mixture.

This is because each color absorbs the same colors that it did alone. If the colors are near each other on the color wheel the different colors absorbed are minimal and the resulting mixture will be relatively bright. If the colors are farther apart the two sets of absorbed colors will cancel out the reflected colors resulting in a duller mix.

There are two ways to lower the saturation of a paint color. One is to add gray paint. If the gray is the same value as the color it is mixed with, lowering the saturation of the color is the only change that will occur. This may sound easy but it is rarely done. More often, an already dull color is added. The problem is that a hue and/or value shift is likely to occur.

The best way to lower the saturation of a color is to mix a little of it's complement with it.

The complement of a color is the color opposite it on the color wheel. Remember that the center of the color wheel is neutral. The chord of the complement mix runs through the center of the color wheel and so the color is neutralized. If you choose an exact complement, you can mix an achromatic gray. By mixing more or less of the complement, you can lower the saturation a lot or a little.

This works because the opposite colors each absorb a portion of the spectrum. If you mix magenta and green the green absorbs all but the colors around green. The magenta (red violet) absorbs all the colors except those around magenta. As a result, all of the colors are absorbed and no color is reflected. When the two colors are exactly matched, black is the result. If there is any white mixed with the paints, the color is gray.

The trick is to know exactly what color is the complement of another. That is what you will learn in this assignment.

Make a stepped scale that goes from one hue to it's exact complement. The two complementary colors will be the only paints used to make the scale. All of the saturation steps must be equal and an achromatic gray must be in the sequence. There must be at least seven steps in the scale.

In this saturation scale the complements are cyan and red. Any set of complements can be used for your value scale. With different colors there might be more or fewer steps between the hues and gray.
A saturation scale demonstrates the effects of mixing complementary colors together. You will learn some of the finer points of color adjusting and will mix an achromatic gray using colored paints. The first step is to find an exact set of complements. You will then construct a scale that goes from one hue to it's complement in a series of steps with gray in the middle.



Do not use yellow/blue (violet) for this project.

There are an infinite number of complementary color sets. The easiest to use will be a set that you have one of the colors for already. Any bright color from your paint box will do if it is a light or middle value (it is difficult to read the gray if dark colors are used). The magenta or cyan that you mixed for your color wheel will do fine. The yellow/violet set is the most difficult to neutralize since gray (or black) and yellow paints mixed together make green, not brown which is dull yellow.

Look at your color wheel and find where the first color is on it. You will mix the color that is exactly opposite to it on the wheel. A word of caution: exactly means just that. If the colors are only slightly off the mix will be a chromatic gray -- they will be a dull color, not gray. You will need the exact match that produces an achromatic gray when mixed.
Try staring at a color swatch for several seconds. When the edges of the color start vibrating look at a neutral background (light gray or white). You will see an "after image" that is the complement of the first color.

Start by mixing a small quantity of the color you believe will work. You will need enough to paint the series of chips in the scale, so err on the side of generosity. Keep this puddle of paint uncontaminated and away from the color mixing area of your palette.

Mix a small sample of the new color with the first hue and see how gray the mix is. Add more of one or the other until the results are as gray as possible. If you get a dull color rather than gray, determine what color you have mixed. Add a little of the color that is in the direction on the color wheel that you desire the mixture to go. This is like navigating on the color wheel and will become natural after a time.

Continue adjusting the complementary color until a gray mixture results when you add it to the original hue.
after finding the set of complements do not change either of the starting colors or add any other colors to the mix.

Now that you have the raw materials, you need to make a number of chips that represent the sequence of colors that occur between two complementary colors. Make a good chip of each of the two starting colors. Then start with one color, add a little of the complement, and paint a new chip (a slightly grayed version of the first color). Add some more of the complement and paint another, continuing in this manner until you reach gray. Keep doing the same thing until you get a slightly grayed version of the second complementary color. You may have to do the same thing starting with the second color to get a complete transition.

Cut one edge of the chips like you did with the value scale and overlap them to choose the best sequence. You may use any number of steps between the complements but the steps in saturation between each chip should be the same and an achromatic gray must be in the sequence. There will be more steps between the brighter color and gray.

Look for fluting in the chips. This phenomena occurs with all three color characteristics: value, hue and saturation.



A colored background would change the appearance of the colors, particularly the neutral colors.

It is possible to make a chromatic gray look more neutral with the right background and a good understanding of the interaction of colors.




This exercise shows how you can decrease the intensity of a color by adding it's complement and gives an indication of how much of each color does the trick.

Mount the chips in the correct sequence in a horizontal pattern and put against a neutral background will show off the results.

It is possible to be more creative, but be logical. The scale must be easy to read and have all of the chips touching each other in the correct sequence.


This project should be labeled SATURATION. Make sure the label is facing the same direction as the artwork. If your Saturation Scale is presented horizontally so that you have to turn the book to see it, the label should read correctly when you turn the book.


You should now be able to mix any color. Start by making the hue using two colors that are on opposite sides of the one you want on the color wheel. Next adjust the value by adding either black or white paint. Finally lower the saturation by adding the complement of the color.

In the real world few colors are as bright as those you can mix and almost all of the colors in a painting need to be lowered in saturation. Overly bright colors is a characteristics that often gives away a novice painter..


© 2006 James T. Saw
Do not copy or reuse these materials without permission.