Color Theory 101

If I’m going to criticize other peoples’ color theory summaries, I figure it’s only fair for me to offer my own.

Note that in this post, I will talk about color on a pretty theoretical level. To learn more about paint itself and its properties, see my post Watercolor Paint 101.

Hue, Value, Chroma

There are three distinct aspects of color:

• Hue – category such as red, yellow, etc.
• Value – light to dark
• Chroma –  vibrant to muted

Here’s how to vary each of them in paint:

• Value: Strong, thick paint is at its maximum darkness. In watercolor, add water (dilute) to make lighter values (the white of the page will show through). In other forms of paint, add white to get a lighter value.
• Hue and chroma: Can be changed by mixing paints together or switching to a different paint.

Why would you want to vary them? Lots of reasons:

• Variation of any kind creates interest.
• Use contrast to draw focus and create emphasis. For example, if most of your painting is dark, a light area will stand out.
• Create a sense of depth.
• Create a sense of light, shadow, and three-dimensionality (especially with value).

Primary Colors

The primary colors are those that cannot be mixed. In physical media such as paint and ink, these are:

•     Yellow
•     Magenta
•     Cyan

If you mix all three primary colors, you get black.

Complementary Color Pairs

Complementary colors are opposites. The complementary color to any primary color is a mix of the other two primary colors.

Primary Color	Complement
Yellow	Blue-Violet
Magenta	Green
Cyan	Red-Orange

Applications in paint mixing

When mixed together, complementary colors neutralize each other, or mix gray/black. When you mix two complementary colors, e.g. red-orange + cyan, you get neutral gray.

In the example below, I use Pyrrol Scarlet as my red-orange and Phthalo Blue Green Shade as my cyan.

You can also use complements to mix a lower-chroma version of either color, e.g. just a little cyan makes increasingly grayed version of the red-orange.

In reality, pairs of mixing complements (two pigments that mix neutral gray) may or may not be exactly the same as visual complements, because pigments never do quite match the idealized hues from color theory. For examples of mixing complements, see my post Mixing Gray & Black in Watercolor.

Color Wheel

A model of arranging hues in a circle in roughly the order in which they appear in the visual spectrum, with complementary colors across from each other. You can find the complement of any color by tracing a straight line across the wheel.

Mixing across the wheel will neutralize your mixes (mix gray). In general, the closer together two colors are the color wheel, the higher-chroma the mix will be.

Color Wheel with Chroma

The most useful color wheels also visualize a pigment’s chroma, with the brightest colors being on the outside of the wheel and duller colors on the inside of the wheel. For example, see Bruce MacEvoy’s Artists’ Color Wheel. You can generate a color wheel of your paints on ArtistPigments.org.

You can choose different settings for the colorspace, which is the algorithm for deciding where to place different colors in the wheel. I find the CIECAM, which Bruce MacEvoy uses, is the most useful and gives my colors the most pleasing spread.

Here’s a tip for using a color wheel with chroma, which I got from Claire Giordano’s Beginner class. You can predict the chroma of a mix by drawing a line between the two components. If the line gets close to the middle of the circle, it will be a low-chroma mix. If the line stays away from the middle of the circle, it will be a high-chroma mix.

For example, if I draw a line between Hansa Yellow Medium and Cobalt Turquoise…

This doesn’t get close to the middle, so it will be a high-chroma mix.

But if I draw a line between Phthalo Green and Quinacridone Violet…

This is much closer to the middle, so it will be a low-chroma mix.

Of course, if I mix anything with black, which is right in the middle, it will be a low-chroma mix.

Color Contrast

These three aspects of color can be used to create interesting contrast in your piece.

Value Contrast: Light and Dark

Using a full range of values can help to give your scene structure and three-dimensionality.

Hue Contrast: Complementary Colors

Juxtaposing two complementary colors can create contrast, enhancing the brightness of each.

Chroma Contrast: Bright and Muted

Additionally contrasting bright colors with muted ones can help the bright colors to stand out.

Key Points

• Color can be described in three dimensions:
  • Hue (what color?) – adjusted by mixing
  • Value (how light or dark?) – adjusted by diluting
  • Chroma (how bright or gray?) – adjusted by mixing
• The primary colors (hues that cannot be mixed) are yellow, cyan, and magenta.
• For high-chroma mixes, mix high-chroma paints that are close together on the color wheel.
• For low-chroma mixes, you can:
  • Mix high-chroma colors across the color wheel (complementary colors)
  • Mix all three primary colors
  • Mix with a low-chroma color
• You can use the color wheel to see which colors are close or far apart on the color wheel, or to design attractive color schemes for your art piece.