The ability to mix colors is fundamental to painting and other visual arts. With just a few primary colors, an artist can create a vast array of secondary and tertiary colors. But which primary colors can be combined to make any desired color? The most common primaries are red, yellow, and blue, but can these three colors really be mixed to create all possible hues?
The Primary Colors
The primary colors are a set of colors from which all other colors can be obtained through mixing. There are several different color models that use different primary color sets, but the most common for art and design are:
- Red, yellow, and blue (RYB)
- Cyan, magenta, and yellow (CMY)
- Red, green, and blue (RGB)
The RYB primary colors are the traditional primaries used by artists for centuries. They provide intuitive, visually balanced color mixing. CMY are the primaries used in color printing and design applications. RGB are the primary colors of light used in color television and computer displays.
While technically different, the primaries all serve the same purpose: to provide a basic palette that can be mixed to create a wide gamut of colors. But how effective are red, yellow, and blue specifically at creating any desired hue?
Mixing Colours from RYB Primaries
When red, yellow, and blue paints or pigments are mixed together, they create secondary colors as follows:
- Red + Yellow = Orange
- Yellow + Blue = Green
- Blue + Red = Violet
Mixing two secondary colors creates the tertiary colors:
- Orange + Green = Olive Green
- Orange + Violet = Red-Violet
- Green + Violet = Blue-Green
With various combinations and ratios of the primary and secondary colors, a wide range of hues can be obtained. By mixing a color with white or black paint, any shade or tone can be made lighter or darker.
So in theory, red, yellow, and blue pigments can be combined to create any desired color. But in practice, there are some limitations.
Limitations of RYB Mixing
While red, yellow, and blue are capable of yielding a wide palette, some specific hues are difficult or impossible to mix accurately using only these primaries. For example:
- Bright purples tend to get muddy
- Oranges can look reddish or brownish
- Greens tend toward blue-green teal tones
- Yellow-greens and lime greens are not achievable
The RYB primaries generally mix well to create a harmonious, vibrant palette. But they lack the exact hue mixing capabilities of other primary sets like CMY or RGB. Professional artists will often augment their RYB palette with additional tube colors to fill in mixing gaps.
Some examples of extra pigments commonly used include:
- Cadmium red
- Cadmium yellow
- Cobalt or cerulean blue
- Viridian or phthalocyanine green
- Dioxazine purple
With a palette expanded in this way, nearly any exact hue can be mixed as needed.
RYB vs. CMY and RGB Primaries
Unlike RYB pigments, the CMY and RGB primary colors can be mixed to create essentially any hue across the visible color spectrum. This is because they mix in an additive way, with each primary adding more wavelengths of light. RYB is subtractive mixing, where each pigment subtracts wavelengths by absorption.
For example, mixing pure red and green light yields yellow light. But mixing red and green pigments results in a dark muddy brown. The additive mixing of light is more flexible than subtractive pigment mixing.
This means CMY and RGB are theoretically capable of more precise color mixing than RYB. But in art, the visual harmony and intuitive mixes of the RYB palette remains popular. By expanding the primaries with additional pigments, artists can achieve both visual appeal and precise hue mixing ability.
Color Mixing Experiments with RYB
The best way to understand the possibilities and limits of RYB color mixing is to experiment hands-on with paints or other pigments. Here are some examples you can try:
Mixing a Spectrum
Try mixing a continuous spectrum from red to violet using only red, yellow, and blue paints. Can you achieve a smooth transition of hues? Or do certain shades seem to be missing?
Mixing a Bright Cyan
Mixing pure green and blue RYB pigments will make teal or blue-green, but not a vivid cyan. Can you mix an approximation using complimentary orange to brighten the green?
Mixing a Lime Green
The yellow bias of RYB green makes mixing a bright lime green difficult. Try adding a lemon yellow and white to dark green. Can you achieve a satisfactory lime?
Mixing a Pure Purple
Red and blue mix to a muted violet. Can adding white bring the purple closer to a pure hue? Does black or grey darken it without muddying?
Through color experiments like these, you can get a feel for the possibilities and limitations of the RYB primaries. Augmenting them with additional pigments expands your mixing versatility.
Conclusion
Red, yellow, and blue are classic primary colors that can mix a wide range of hues for painting and design. While they have some mixing limitations compared to CMY and RGB, their visual harmony and history make them a popular primary palette. By thoughtfully expanding an RYB palette with secondary pigments, artists can mix virtually any desired color with precision. The next time you pick up a brush, experiment with blending reds, yellows, and blues to see the colorful possibilities.
