Color Theory Part 1- What Is Color?

Unsplash, CC0

Why Care About Color Theory?

Lately, I have been taking a deep dive into color theory because I feel that an understanding of these concepts will be helpful for me to grow as an artist. If you have ever dabbled in this field before, you will know that it can get heady fairly quickly. My goal with this series of blog posts is to filter through the information and report back what I think is most relevant and helpful to creatives or anyone who is curious about color.

This particular post goes into what is color, the electromagnetic spectrum, how we see color, how not all creatures see the same colors, and how the brain is really the driver of color perception. Future posts will go into additive and subtractive colors, different color theories (not everyone agrees!), color wheels, and features of colors that can help artists and creatives to select colors more thoughtfully.

What Is Color?

This is really a tricky question to consider. The fact is that color wouldn’t exist without light, which reflects off of objects depending on their chemical composition to help us to see color. Additionally, we wouldn’t see color if it weren’t for the photoreceptors in our eyes that provide information to our brains to tell us what color we are seeing. The study of color is called chromatics, colorimetry, or color science. One of the best-known pioneers of color science was Sir Isaac Newton.

Sir Isaac Newton and His Color Experiments

In the 1660s, Sir Isaac Newton was the first person to discover that the light from the sun, which appears white when coming through a window, is actually made up of several colors. He made this observation by using a prism, which refracted the sunlight into its components that can be seen with the human eye. His findings went against the predominant theory of that time, which said that color was a mixture of lightness and darkness.

Sascha Grusche, CC BY-SA 4.0, via Wikimedia Commons

Newton’s Spectrum of Light

The spectrum of visible light that Newton discovered is a continuous line, meaning that each color doesn’t have a specific break before the adjacent color. To keep things simple, he created 7 distinctions and named them to line up with the number of musical notes in an octave and the days in the week. It is because of him that as children we learned ROY G BIV (red, orange, yellow, green, blue, indigo, and violet). More recently, color scientists removed indigo, and so present-day spectrums contain just 6 colors.

Newton’s Color Wheel

Newton discovered that if he mixed red and violet the result would be magenta which wasn’t on the spectrum. So he created a circle to help determine what would happen if you mixed colors. The outcome was the very first color wheel. Varying color wheels have been invented since Newton’s wheel which was created in 1666.

A key component of Newton’s theory is that black is the absence of color, and that white is the presence of all colors. Because of the later principle, sunlight is called additive. It is the sum of all of the colors. In the next blog post, I will explain the difference between additive and subtractive colors.

Isaak Newton, Public domain, via Wikimedia Commons

Sunlight and Our Eyes- How We See Color

The Electromagnetic Spectrum

The sun gives off electromagnetic energy in the form of ultraviolet rays, visible light, and infrared wavelengths. Visible light refers to the energy that can be seen by humans, which is what Newton was able to capture using his prism.

The portion of the electromagnetic spectrum that the human eye can detect is quite small (400- 700 nanometers) and is depicted below by the rainbow in the middle.

Solar Radiation of Four Wavelengths in Spectrum, Ali Tahouri

Photoreceptors in Our Eyes Help Us to See Color

Most of the energy moving about cannot be seen by humans, such as ultraviolet rays and microwaves. The reason why we can see energy in the visible spectrum is because of photoreceptors in our eyes. Cone cells help us to see color, while rod cells help us to differentiate between lightness and darkness. Most humans have three types of cone receptors: “L” cones, which stands for “long” because they recognize red light which has a long wavelength. “M” cones perceive green, which has a middle wavelength size, and “S” cones decipher blue, which is the shortest wavelength, next to violet.

Simple Description of How We See Color

Look at the image below to get a basic understanding of how we see the red of an apple. When sunlight hits an object like an apple, only a portion of the visible spectrum is reflected. All other light is absorbed because of the chemical composition of the apple. In the case of the apple, the long wavelengths bounce off, which triggers the “L” photoreceptors. Finally, the receptor’s information is interpreted by the brain, which tells us that the apple is red.

Wade A and Benjamin A, CC BY 3.0, via Wikimedia Commons

The Bottom Line- It Is the Brain that Perceives Color

Variations In What Humans See

All animals that can see color, perceive it because of two things: a light source is bouncing off of an object and photoreceptors translate that information in the brain.

Ultimately, it is the brain that determines the color we see. Most humans have 3 types of cones and can see blues, greens, and reds. But some humans who are colorblind, have 2 functioning types of cone receptors and may not be able to distinguish between green and red or yellow and blue. To further complicate things, 12% of females have 4 types of cones, which enable them to see even more color.

Learned Colors May Not Look the Same to Everyone

This means that not all people see color in the same way. Additionally, there may be some variations in perception of what each of us sees as a certain color. For example, when a child is taught that an object is “blue”, he will learn to call other objects with a certain hue blue as well. But each person’s blue may appear differently to them depending on their brain’s translation. It may help to explain why we have different tastes and preferences.

Change in Season Impact Color Perception

Many other factors can impact how we see color such as the change in seasons. An experiment was performed in York, England in January and June to test participants’ perception of a pure yellow hue. The study was published in the Current Biology journal in 2015. The test subjects’ definition of yellow shifted to more of a greenish-yellow in summer, which is comprised of shorter wavelengths. During winter the definition of yellow shifted to a reddish-yellow, which is made up of longer wavelengths.

Previously Viewed Subjects May Impact Color Perception

What a person has looked at previously can impact the brain’s ability to perceive color as well. John Sadowski came up with an illusion that proves this point. The .gif below shows a two-colored version of a Spanish castle that flicks to a black and white version of the same castle. Stare at the black dot in the first image for 20 seconds, and then when the picture switches to the black and white version, you will see it in color. This image underscores the fact that the brain is quite complex when it comes to color perception.

Emotional and Cultural Ties to Colors Impact Perception

Finally, humans also tend to put emotional significance on colors based on culture and experiences. For example, we tend to associate the color blue with sadness and red with anger. Or similarly, we associate orange with warmth and blue with cool. I will delve into these concepts in future blog posts in this series.

All of these factors influence how we see color and ultimately will impact our art as well. Understanding these principles can help us to use our creative powers to be more expressive and thoughtful when choosing colors for artworks. Whether it will help us to get across a message more effectively or to create a more pleasing color composition, I hope you enjoyed this blog and that you will stick with me as I continue to explore color theory.

Let me know your thoughts in the comments below.