There are two ways in which we mix color: Additively, using direct light from an original source, and Subtractively, using light reflected from substances and surfaces. When we work with light, we are in the additive color system. When we work with inks, paint, crayons, food colorings, dyes, etc., we are using the subtractive color system. The two systems are related, but the colors in each system follow separate rules.

Designers, illustrators and photographers need to understand both types of mixtures in order to get the best possible color result.

Prior to the age of digital design the study of color and color mixing focused on using pigments. With the digital age we have become aware that color mixes not just physically but optically, and the study and use of color is far more complex than ever.

Subtractive Color Mixing

Subtractive mixing is the process of mixing 2 or more colors together to achieve a third color, and then applying that color to the paper or paint surface. So we would makes yellow and red primaries to create orange. We can mix orange with white to create a peachy tint. We can mix orange with black to create a burnt orange shade. And we can mix orange with gray — both white and black — to create subdued colors (tones). We can mix orange and its complement, blue, to create a variety of browns earth tones, and in the right balance, a true gray.

The subtractive process removes color from the light. The pigments filter the light. Each time pigment colors are mixed together in this subtractive manner they lose some visual strength because less light is reflected. The resulting mixture will be less robust than the colors that were used to create it.

In the subtractive mixing, colors blend together and filter the light. The resulting colors do not reflect light perfectly, which is why what you see on your computer screen does not look like what you print out in hard copy. Subtractive colors (ink pigments) do not filter the light perfectly.

Additive Color Mixing

Optical mixing, also known as optical fusion, was explored creatively by the Impressionists painters. Georges Seurat, Claude Monet, Honore Pettijean, among others, applied small patches of subtractive colors (paints) to their canvases, that with distance, fused visually to created new colors that didn’t exist on the paint surface. This knowledge of optical fusion is the basis for color printing and digital color.

Optical mixture is a form of partitive color mixing. Our eyes will blend all the colors we see into an averaged result. When we get closer to the object or surface, we will see the individual colors that have mixed together. Small amounts of black intermingled with small amounts of white will fuse into gray — the average of the black and white. Looking at a grassy field, we will see the whole field as being green, but if we look up close at individual blades of grass and everything else that’s in the lawn, we will see a variety of colors, and not just greens, but blues, reds, browns and yellows.

Why Color Training Matters

The average person averages color. A trained eye can identify the colors with in the colors they are seeing. They can break them down into proportions of the primary colors, plus black and white and variations of gray. The trained person is able to perceive subtle variations in colors from the same hue family, and and see the difference between scarlet and crimson (both are in the red hue family), and between cadmium yellow and hansa yellow. They’ll be able to use fully-saturated colors hues, tints, shades, tones, and chromatic and achromatic neutrals for specific purposes.

One of the most basic questions that artists and illustrators have is, “How do I mix that skin color?” By understanding how colors mix, they are able to look at any skin tone and break it down into its color parts, and then create mixtures of pigments that are accurate to the base skin color. They can also create believable colors for shadows, highlights, and areas of reflected light.

Color enriches our lives and helps us communicate. It is the most complex of the formal design elements. Color is light, and our perception of it is affected by surface qualities and light qualities. To see anything is to see color. Color is fundamental to our human experience. It brings us pleasure. It identifies. It expresses our moods. It helps create brands.

Understanding how color mixes is crucial for visual designers and graphic communicators.

Resources for Further Study About Color Mixing

Designing for Color Blindness — Aaron Tenbuuren on Medium

How I Learned About Color Mixing — Julia Lundman on Medium

Color Mixing Tool — on Try Colors

What questions do you have about color mixing?

Are there any particular issues you need help with? I’d love to hear from you in the comments below.