Most of us learn at some time in elementary school that we can make almost any color from some mixture of the primary colors red, yellow, and blue. Artists and aspiring artists around the world use the red-yellow-blue or RYB color model to create pigments when the exact colors are not available.
There is also a color model called RGB that can be used for electronic visual displays, so the RYB color model isn’t the very latest understanding of how to create colors—electronic displays use lights to combine red, green, and blue, but the RYB color model is still important in the visual arts.
What Is the RYB Color Model?
The RYB color model is a subtractive method of creating every possible visible color. When the three primary colors red, yellow, and blue are mixed in equal amounts, the result is a dark brown color. As red, yellow, and blue pigments are removed from the mix, other colors are visible.
The reality of how vision works is that the color we see is really the one color that an object isn’t. We only see the wavelength of light that is reflected from an object, not all the other wavelengths of light that it absorbs. But for purposes of the RYB color model and the creation of pigments, we are only concerned with how pigments reflect light.
Why Is RYB Color Theory Important?
The earliest artworks we know about are cave drawings. Their prehistoric artists were limited to a single color, usually black or ochre. Fast forward thousands of years and the black and white remained the same in medieval illuminated manuscripts, but the artists of the time were able to add flat fields of gold, red, and blue. A few centuries later, the paintings of the Renaissance demonstrate not just a new understanding of light, shade, and perspective, but also a broader range of pigments.
Renaissance artists did not have, however, their own RYB color theory. Some paintings of the era were never finished because artists could not afford the expensive pigments they needed to add the colors they wanted to their canvas.
The color ultramarine, for example, was so expensive that artists could not buy it. Their wealthy patrons had to buy it for them. Contracts for paintings specified which figures in the painting would be done in ultramarine and how much ultramarine would be used around each figure, to keep artists from hoarding the pigments for other work.
Even inexpensive colorants were a problem. Some pigments reacted with each other and produced disastrous results. Artists had to plan their paintings so certain pigments never overlapped or came close to each other. And getting even the colors that were available at the time could require hunting for a rare berry, or grinding down poisonous rocks, or visiting the local alchemist.
The reason the art world remained stuck in the limitations of primitive pigments came from a theory inherited from ancient Greece. Classical philosophers believed that the colors were different mixtures of black and white. Yellow, for instance, was thought to be a little darker than white, and blue was thought to be a little lighter than black. Red and green were thought to be in the middle of the light-to-dark spectrum.
This theory did not inspire anyone to mix colors, only to search for unique pigments. As recently as 150 years ago, artists did not have easy access to colors that did not react with each other in undesirable ways. All of this changed with the development of RYB color theory.
How RYB Color Theory Became a Foundation of Modern Artistic Technique
In the 1600s, artists began thinking in terms of red, yellow, and blue as primary colors. They noticed that combining these pigments, if there wasn’t some kind of undesirable reaction, could make the secondary colors orange, green, and purple.
In 1704, Isaac Newton wrote in Opticks that black and white weren’t colors at all. There was no spectrum of color running from black to white.
Instead, Newton recognized that certain pairs of colors resonate when they are placed beside each other. Green and red, as well as blue and orange, reinforce each other when painted side by side. Today, this is known as complementary colors.
It wasn’t until nearly 140 years later that a French chemist named Michel Eugène Chevreul used Newton’s color theory to create a systematic method of making any color from the three primary colors. His work led to the creation of the color wheel, which easily explains how to use primary colors to create every other color.
The Science Behind RYB Color Theory
Modern physics explains how RYB color theory works. Every color corresponds to a specific wavelength of visible light, measured in billionths of a meter, also known as nanometers, or nm. Since light has a constant velocity of approximately 186,000 miles per second, this also means that every color has its own frequency, measured in terahertz, abbreviated THz, or trillions of times per second. Different colors involve different amounts of energy in the photons of light reflected by the color, measured in electron volts, or ev.
Light, you probably learned in science class, is both a particle and a wave. Waves can reinforce or cancel out each other.
Why does that make a difference?
Here is an example:
Orange light has a wavelength of 600 nm. However, adding red light, which has a wavelength of 700 nm, to yellow light, which has a wavelength of 580 nm, creates orange light, with a wavelength between the two.
You don’t need an orange pigment to create an orange color. RYB color theory relies on the fact that different colors have different wavelengths, frequencies, and energies.
There are two problems with this approach. Different colors mean different things to different people. If you look at the chart above, you will notice that there is a range of frequencies for each color. RYB color theory doesn’t create an absolute color that everyone will see the same way every time. Even electronic devices that rely on LEDs or cathode ray tubes to create specific wavelengths of light won’t always be seen the same way by different people. Our emotions affect the way our brains interpret the information that our eyes send them.
The other factor not considered in the RYB model is that colors are not always pure. They can be mixed with white. Red mixed with white creates pink, for example. Red and pink are the same hue, but they have different saturations. This makes a difference when the surfaces to which the different hues are applied receive illumination with different intensities of light. A color may look redder in dim light but pinker in bright light.
The RYB color wheel is nonetheless an extremely useful tool for artists creating their own colors for their audiences.
Important Things to Remember About the RYB Color Model
There are some very basic facts to keep in mind about the RYB color model to make use of it in art and painting. We will be repeating some information from earlier in this article, but it is worth repeating because it is important.
- The RYB color model is a guide for mixing paints and pigments to create new colors. It is not the model used for designing websites or enhancing online user experience (U/X).
- The initials of the RYB color model come from its primary colors, red, yellow, and blue. It is not the same as the RGB red-green-blue model used in electronic displays.
- When red, yellow, and blue paints are combined, they create other colors. In the RYB color model, the other colors are orange, green, and purple.
- Artists make secondary colors when they add primary colors in equal proportions. Adding all three primary colors together in equal proportions creates dark brown.
- When the two or more of three primary colors are mixed in unequal amounts, they produce different colors.
- There is no single red, yellow, or blue that applies to every use of the RYB color model. Different artists will have different reds, yellows, and blues. However, the primary colors can be defined in terms of precise wavelengths of light to create an absolute color space.
It’s natural to wonder why we need a color model, when there is a paint available in every imaginable color and hue. The RYB color model is still important to artists because it:
- Helps make sense of the changing colors seen in nature.
- Explains the relationships of colors to each other.
- Shows how to mix colors with predictable results.
- Organizes the colors by name, codes, and formulas.
- Forms the basis of rules for the successful use of colors.
- Creates color palettes and color guides.
Why Use the RYB Color Model?
- The RYB color model makes sense of the results when different colored paints are combined.
- The RYB color model helps artists relate objects and sources of light.
- The RYB color model helps artists deal with the fact that colors feel and look different depending on context.
- The RYB color model helps artists manage colors when their works are illuminated by different sources of light, used on different media (for example, fabric versus canvas), or shown outdoors versus indoors.