Color is fundamental to many forms of art. Its relevance, use and function in a given work depend on the medium of that work. While some concepts dealing with color are broadly applicable across media, others are not.
The full spectrum of colors is contained in white light. Humans perceive colors from the light reflected off objects. A red object, for example, looks red because it reflects the red part of the spectrum. It would be a different color under a different light. Color theory first appeared in the 17th century when English mathematician and scientist Sir Isaac Newton discovered that white light could be divided into a spectrum by passing it through a prism.
The study of color in art and design often starts with color theory. Color theory splits up colors into three categories: primary, secondary, and tertiary.
The basic tool used is a color wheel, developed by Isaac Newton in 1666. A more complex model known as thecolor tree, created by Albert Munsell, shows the spectrum made up of sets of tints and shades on connected planes.
There are a number of approaches to organizing colors into meaningful relationships. Most systems differ in structure only.
Traditional Model
Traditional color theory is a qualitative attempt to organize colors and their relationships. It is based on Newton's color wheel, and continues to be the most common system used by artists.
Blue Yellow Red Color Wheel
Traditional color theory uses the same principles as subtractive color mixing (see below) but prefers different primary colors.
- The primary colors are red, blue, and yellow. You find them equidistant from each other on the color wheel. These are the "elemental" colors; not produced by mixing any other colors, and all other colors are derived from some combination of these three.
- The secondary colors are orange (mix of red and yellow), green (mix of blue and yellow), and violet (mix of blue and red).
- The tertiary colors are obtained by mixing one primary color and one secondary color. Depending on amount of color used, different hues can be obtained such as red-orange or yellow-green. Neutral colors (browns and grays) can be mixed using the three primary colors together.
- White and black lie outside of these categories. They are used to lighten or darken a color. A lighter color (made by adding white to it) is called a tint, while a darker color (made by adding black) is called a shade.
A more quantifiable approach to color theory is to think about color as the result of light reflecting off a surface. Understood in this way, color can be represented as a ratio of amounts of primary color mixed together.
Additive color theory is used when different colored lights are being projected on top of each other. Projected media produce color by projecting light onto a reflective surface. Where subtractive mixing creates the impression of color by selectively absorbing part of the spectrum, additive mixing produces color by selective projection of part of the spectrum. Common applications of additive color theory are theater lighting and television screens. RGB color is based on additive color theory.
- The primary colors are red, blue, and green.
- The secondary colors are yellow (mix of red and green), cyan (mix of blue and green), and magenta (mix of blue and red).
- The tertiary colors are obtained by mixing the above colors at different intensities.
Additive Color Representation
The primaries are red, green and blue. White is the confluence of all the primary colors; black is the absence of color.
Subtractive color theory ("process color") is used when a single light source is being reflected by different colors laid one on top of the other. Color is produced when parts of the external light source's spectrum are absorbed by the material and not reflected back to the viewer's eye. For example, a painter brushes blue paint onto a canvas. The chemical composition of the paint allows all of the colors in the spectrum to be absorbed except blue, which is reflected from the paint’s surface. Subtractive color works as the reverse of additive color theory. Common applications of subtractive color theory are used in the visual arts, color printing and processing photographic positives and negatives. The primary colors are red, yellow, and blue.
- The secondary colors are orange, green and violet.
- The tertiary colors are created by mixing a primary with a secondary color.
Subtractive Color Mixing
The primaries are blue, yellow and red
Color Attributes
There are many attributes to color. Each one has an effect on how we perceive it.
- Hue refers to color itself, but also to the variations of a color.
- Value (as discussed previously)refers to the relative lightness or darkness of one color next to another. The value of a color can make a difference in how it is perceived. A color on a dark background will appear lighter, while that same color on a light background will appear darker.
- Tone refers to the gradation or subtle changes made to a color when it’s mixed with a gray created by adding two complements (see Complementary Color below). You can see various color tones by looking at the color tree mentioned in the paragraph above.
- Saturation refers to the purity and intensity of a color. The primaries are the most intense and pure, but diminish as they are mixed to form other colors. The creation of tints and shades also diminish a color’s saturation. Two colors work strongest together when they share the same intensity. This is calledequiluminance.
Beyond creating a mixing hierarchy, color theory also provides tools for understanding how colors work together.
Monochrome
The simplest color interaction is monochrome. This is the use of variations of a single hue. The advantage of using a monochromatic color scheme is that you get a high level of unity throughout the artwork because all the tones relate to one another. See this in Mark Tansey’s 'Derrida Queries de Man' from 1990.
Analogous Color
Analogous colors are similar to one another. As their name implies, analogous colors can be found next to one another on any 12-part color wheel:
Analogous Color, 11 July 2012, Creator: Oliver Harrison
Licensed under a Creative Commons Attribution 2.5 Generic License
You can see the effect of analogous colors in Paul Cezanne’s oil painting ‘Auvers Panoromic View’.
Color Temperature
Colors are perceived to have temperatures associated with them. The color wheel is divided into warm andcool colors. Warm colors range from yellow to red, while cool colors range from yellow-green to violet. You can achieve complex results using just a few colors when you pair them in warm and cool sets.
Warm cool color, 11 July 2012, Creator: Oliver Harrison
Licensed under a Creative Commons Attribution 2.5 Generic License
Complementary Colors
Complementary colors are found directly opposite one another on a color wheel. Here are some examples:
- purple and yellow
- green and red
- orange and blue
Complementary Color, 11 July 2012, Creator: Oliver Harrison
Blue and orange are complements. When placed near each other, complements create a visual tension. This color scheme is desirable when a dramatic effect is needed using only two colors. The painting Untitled by Keith Haring is an example.
You can click the painting to create a larger image.
A split complementary color scheme uses one color plus the two colors on each side of the first color’s complement on the color wheel. Like the use of complements, a split complement creates visual tension but includes the variety of a third color.
Split Complementary Color, 11 July 2012, Creator: Oliver Harrison
Color Subtraction refers to a visual phenomenon where the appearance of one color will lessen its presence in a nearby color. For instance, orange (red + yellow) on a red background will appear more like yellow. Don’t confuse color subtraction with the subtractive color system mentioned earlier in this module. Color subtraction uses specific hues within a color scheme for a certain visual effect.
Simultaneous Contrast
Neutrals on a colored background will appear tinted toward that color's complement, because the eye attempts to create a balance. (Grey on a red background will appear more greenish, for example.) In other words, the color will shift away from the surrounding color. Also, non-dominant colors will appear tinted towards the complement of the dominant color.
Color interaction affect values, as well. Colors appear darker on or near lighter colors, and lighter on or near darker colors. Complementary colors will look more intense on or near each other than they will on or near grays (refer back to the Keith Haring example above to see this effect).
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