Note: These files were created in the CMYK colorspace for printing on a CMYK printer, therefore the RGB files are the result of export from CMYK. This may create technical issues in RGB, depending on your usage.[1] If you require accurate RGB representation, it is recommended to construct your color wheel originating within the RGB gamut. These colors are machine color.
.png
570 KB
.png
94 KB
.png
603 KB
.png
97 KB
application
Practical applications of this topic for artists can be found in Keeping a Sketchbook: Understanding Watercolor Paint, instructed by Dr. Arthur Witulski at Vanderbilt University, who included this color wheel theory in his art curriculum.
discussion
Do yellow and blue make green?
As many a frustrated kindergartener finds out, not exactly. The truth of the physical world does not always conform so neatly to our models, no matter how entrenched those ideas might be.
This project will explore one of these models, the artist’s color wheel — taught through centuries in the atelier as fact. But like many things passed down through rote tradition, this model could use a bit of freshening up — updated with some scientific understanding coming out of the science of neurology.
the problem
Some contemporary artists are beginning to challenge the traditional artists’ color wheel, particularly in light of their own personal experience with commercial printing processes.[2] Having seen how it works on the press, they are forced to reconcile this understanding of color as it relates to the traditional artist color wheel they’ve been taught in art school. Exploring these results also begins to address the challenges presented by the limitation of pigments themselves — more specifically, the constituent metals and chemicals that give pigment its color.
The artist’s goal is to create a more accurate color wheel theory.[3]
The traditional color wheel is not wrong, just missing something. A deficiency for which we cannot be blamed, just coming from our natural blind spot. The result of our exploration will reflect a model closer to how the phyiscal world operates.
how we got here
The painter’s conception of color has changed over time with the changes in perceptions brought by scientific understanding. Think of the Impressionists and their new way perceiving light in a scene. Have you noticed how before the paintings of the Impressionists, outdoor scenes looked, well, like they are happening inside somewhere?
By opening the door of the atelier — literally — and taking the easel outside, the Impressionists discovered new perspectives of how light appears on the surface of objects. After they did that, the old ways of doing things, while respected, just could not keep up with how we actually “see” reality.
The traditional color wheel that we looked at before, from the famous Farbkreis version, comes from the philosophy of color that evolved in the atelier. Taught in the studios of the old masters, this traditional color wheel is still taught in art schools today — sometimes as a historical foundation, but too often as canon. Yet in the same way the Impressionist painters helped us perceive the light outside in a more accurate way, the traditional color wheel itself must too yield to a more contemporary understanding of how the human eye perceives what we call color.
what is color?
prisms, electromagnetic spectrum, wavelengths 380 to 750 nm, 790–400 terahertz
via davidsancar
Visual “colors,” as we understand them, are not physical objects on a rainbow per se, but are actually symbols created in our minds as the brain interprets the wavelengths perceived by the photoreceptor cells of the eye. The visible part of the wavelengths are detected from frequencies mixed “out there” in the world by way of two primary attributes: reflective light and transmissive light.
Let’s explore the difference.
| Reflective Light | Transmissive Light | |
|---|---|---|
| ☇☇ ☼ | ☼ ➙ | |
| Color Model | subtractive | additive |
| Color Primaries | cyan, magenta and yellow (CMY) |
red, green and blue (RGB) |
| Use Cases | inks on paper; painting on canvas |
projection on screen; images on a computer monitor |
Reflective light refers to the aggregate of wavelengths that first bounces off an object before getting to your eye, like the color represented in a leaf. Transmissive light, on the other hand, is the wavelength of electromagnetic energy emitted by the source light itself, like the light from the sun before it hits the leaf.
Reflective light follows the subtractive color model: source light (like sunlight) comes in contact with the particles of an object (in this example, a leaf) and some of the wavelengths are absorbed — or subtracted — by the molecular structure of the chlorophyll. The unabsorbed wavelengths are reflected back into the world containing only the frequencies of the visible color that reaches your eye, in this case a shade of green. The reflective or subtractive paradigm is in play when you look at a painting made of pigments: the molecular structures of the various metals in the pigments absorb source light and reflect back the resulting frequencies, appearing as color in your mind.
Transmissive light, however, follows the additive color model: that is, the source light itself emerges from the black nothingness by combining — or adding — color frequencies in proportion to the aggregate of the resulting color. This is happening right now as you read this computer monitor. The brain interprets the frequency of this electromagnetic energy and assigns colors associated with that wavelength. The projected light is received directly in the eye and perceived by the brain without having bounced off something.
Yet, but is it actually color that you see?
the curiousness of magenta
Wavelength or frequency itself is not color, even in the so-called visible spectrum. Instead, the mind assigns a symbol to represent the wavelength in your brain. That symbol is interpreted as color. The wavelengths received in the retina are interpreted by the brain, and the brain “shows you” color. That is the structure of our world — it is actually all in our heads.
In fact, when the mind does not have a symbol to associate with the wavelength, it just makes one up. A classic example of this phenomenon is the color magenta. Magenta is not a really color. It is an extra-spectral (meaning, not on the spectrum) “substitute” for a wavelength that the mind thinks should be there, but that does not actually exist in the visible light spectrum. It is not on the rainbow. It is created entirely in the mind.[4]
Can you see this?
prisms, electromagnetic spectrum, wavelengths 380 to 750 nm, 790–400 terahertz
via davidsancar
the CMY/RBG color wheel
While it is important to keep the phenomenon of magenta in mind (and the metaphysical ramifications of making things up that are not there), for artists, the important part is that magenta “exists.” It is the missing piece of the so-called color spectrum that the traditional color wheel has not taken into account. A more contemporary color wheel, however, does take the weirdness of magenta into account. Magenta is, in fact, an anchor of a new model that reconciles the two paradigms of color and wavelength. A model that unifies the common attributes between the additive and subtractive.
And, interestingly, it is done like this:
The outer colors of the projection are the three primary colors of the additive color model: red, green and blue (RGB). As transmissive attributes of color, these primaries are used in contemporary projection techniques (such as television and computer monitors) — projecting from a black-screen source to produce the illusion of the full color spectrum through in-retina visual mixing: all colors “seen” are actually proportional amounts of red, green and blue to simulate the other colors (orange, purple, etc).
As seen in the image above, when the RGB primaries are projected on a white screen, a curious thing happens: the secondary colors produced by the projection are cyan, magenta and yellow. And, interestingly, these are exactly the three primary colors of the subtractive color model.[5] Thanks to the work of James Clerk Maxwell, we know that CMY is a much better arbiter of true color mixing than the primary colors of red, blue and yellow of the traditional color wheel. CMY produces more accurate and predictable color mixing results with inks on white paper.
So our contemporary visual color wheel could have a foundation in this overlap. Magenta can be the elusive “unified field” that reconciles the two paradigms of color and wavelength, between the additive and subtractive. This new color wheel can be constructed from this resultant pattern of the two models combined, with each primary taking its place on an equidistant spot on the wheel and, to complete the circuit, the secondary colors that are created by the visual mixing of the six primary colors, in equal proportion, then fills in the remaining six spaces of a 12-slice pie.
conclusion
The CMY/RGB color wheel (and its correlating grid) represents a good visual model of color for the purposes of studying hue, value and balance of pure theoretical color. The colors represented on the wheel are colors as represented in the transmissive light arena — that is, the additive model. I’d say it also improves upon the traditional artist’s color wheel in terms of visual color complements.
For mixing paint, we need to find the pigment equivalent (subtractive model) to the additive-model colors represented on the color wheel, and then find the complements (or opposites) that can be mixed to create all the colors in between.
There is a color mixing system created by the paint manufacturer Lascaux⎋ that is configured around a 5-color primary model that includes red and blue from RGB, and the CMY colors (cyan, magenta, yellow).[7] They have some color exercises in their product literature, with some starter ratios for common or popular colors, but it does not go the distance as far as creating a mixing color wheel or gradient spectrum. I’ve included some mixing results from their system in my pigments tests, but I have not completed the circuit for a wheel-type complement graph (as it was beyond the scope of my research at the time). I’ve also noticed that some other paint manufacturers are beginning to match their own color spectrums to the magenta color wheel, and I’ve listed some of the brands in a separate comparison chart. Here are some resources.
color mixing Using the Lascaux Sirius primary color system to explore the concepts of additive and subtractive color.
acrylic colors Some notes I took while researching the constituent elements of pigments in acrylic paint.
Posted December 14, 2015
Last updated October 29, 2023