Color Relativity: Color Theory Beyond the Wheel
A lot of resources on color theory like to begin with great detail about the scientific explanations and processes behind color phenomena, and it’s a little important, but only to the extent to which you have some basic comprehension of the entanglement of light, color, and your brain. Here’s what you should know:
The human eye contains rods and cones, which process different wavelengths (colors) of light in different ways. We perceive an object’s color by the wavelengths of light that it reflects, and the object absorbs all the other wavelengths. Side note: Mirrors reflect all wavelengths (pretty much) equally, which is why they're “white.” Actually, they reflect green a little better than the other colors, so mirrors are technically sort of green, but I digress.
There are three properties of color: hue (or chroma), saturation, and value. Value is the most important for discerning form and depth. However, shifts in hue and saturation also correspond to changes in perceived value.
In the absence of light, we cannot discern any color. Consequently, the properties of light in any situation have great influence over the way objects appear.
Color is relative—That is, relative to the light and to the other colors surrounding it. The eye and the brain work in conjunction to compensate for the color of the light on and surrounding an object in order to determine what the color of an object actually is.
When I say that an object is a color, I am referring to the local color of the object. This is one of three theoretical types of color, which are as follows:
- Relative color: The color as it is seen, according to the perception of the eye and the way the brain interprets the information it receives.
- Absolute color: The color as it really is, if one were to, hypothetically, color-pick an area of the object.
- Local color: The actual color of an object. This cannot really be observed, so it must be inferred by the way in which an object appears and the way it reacts to light.
This can all be very confusing at first, so let’s familiarize ourselves with the differences and use these concepts to analyze this piece of artwork by Gimaldinov.
The dark, desaturated blue (absolute color) highlight on the cupid’s bow area under his nose, against the red on the character’s left (absolute color), appears to be much brighter and bluer in context (relative color), and we can tell that the face as a whole is actually red (local color). Your brain figures this out automatically, and if we understand the way in which the brain processes colors we can use this information to create artwork that the brain will perceive as both attractive and convincing. If we make color choices that go against the way these phenomena function it confuses the brain, which can be jarring and might make an otherwise satisfactory image fall flat.
Traditional color theory education often, inadvertently, promotes counterproductive thinking by focusing on the color wheel and on color relationships—complements, triads, that sort of thing. These principles are really only useful for selecting the relative color composition of elements of an image. It’s a lot of rote memorization that’s not very practical, especially because nearly any combination of colors you pull out of your ass will correspond to some sort of relationship. More important than the choice of color scheme are the color proportions and distributions in any image, as well as one’s ability to choose the correct absolute colors to portray those relative color relationships.
The conventional color wheel encourages use of absolute relationships, of putting a bright green next to a bright red to form a complementary color scheme. The problem with this is that when you look at two absolute complements adjacent to one another your mind isn’t able to adapt and compensate properly, which makes the image overwhelming and confusing, as it doesn’t portray any sort of believable lighting situation.
Instead, you should focus on creating the illusion of a complement by using your knowledge of relative color. One thing to remember is that greys will often appear as the relative complement of the surrounding absolute. This means that if you put a grey next to a red, it will appear green. If you put a grey next to a green, it will appear red. This is how you should create the color relationships in your image—by pushing one color further towards the extremes, not both of them.
The comic illustration contained in this post is a good example of how you can imply a contrasting blue and orange color scheme without actually using blue and orange. Of course, some might prefer the dissonant version, since tastes do vary, but the principles that it exemplifies do not change (unless if you're colorblind, and then maybe they do).
Another thing to keep in mind is that since hue and saturation do influence perceived value, you can use this to fudge your colors. If one color isn’t quite working for you in the context of a piece, but the value should stay the same, you can usually make that offending color a little darker and less saturated or lighter and more saturated while still retaining the appearance of the same value. Certain hues also are inherently brighter than others, so you can use hue shifts in a similar way.
Almost as important as the three properties of color and your color composition choices are your color distributions. If you're working with two complements, for example, you probably don’t want to use an equal amount of each. Just like how the brain cannot process two absolute complements, it has trouble compensating for two complements of equal proportion, particularly if the two complements are rendering the same object. As illustrated by this digital painting by lord-phillock, even if your values are pretty solid, the almost equal contrast between red and blue makes it difficult to distinguish what the local color of the character is supposed to be, and it sort of flattens the image. Usually, if you're trying to portray a primary and secondary light source (or fill light) in your image, you'll want your secondary light source to be much less bright than the primary source. This would not only decrease the hue, value, and saturation of the secondary source’s influence on the object, but the light’s physical reach would probably be reduced as well.
Your palette for a piece should have some distinguishable dominant hue or “lean” to it, and in this case there doesn’t really seem to be one. If we push all the colors, particularly those on the blue end of the spectrum as well as the transitory colors, towards yellow, the palette becomes much more cohesive. It’s also apparent that the brightest tone at the blue end of the palette is too bright for a secondary light source and for the purposes of simultaneous contrast. If we darken that secondary light source and apply the new palette to the image with some simple adjustment layers and overlays in Photoshop, the piece already becomes more moody and cohesive.
Especially as a beginner, it can be very tempting to look towards mathematical formulas and rigid step-by-step approaches to picking your colors. Unfortunately, there isn’t any one formula that will work for every situation. Besides the fact that the variables would change depending on the lighting being portrayed and artistic intent, it’s a complicating factor that some hues are inherently brighter than others. (Green is roughly twice as bright as red, and red is about twice as bright as blue.) I'm never fond of the “getting a feel for it” approach to anything, but I think this sort of learning curve is inevitable for a lot of things in the art realm. However, if you understand the general rules under which color operates in reality, you can experiment with your own colors, using this knowledge, until you find something that pleases you.
It’s totally fine—preferable, actually—to bend the rules a little, and push your colors until you have to pull them back again. In fact, creating pixel art with a limited palette is a great opportunity to experiment with your palette, as you'll often come up with unique color combinations out of necessity that you would never have tried otherwise. Also, a limited palette lends art a sense of coherence and, if your colors are thoughtful, atmosphere that gives it some realism as well.
You can still lean on a color wheel by using something like Gurney’s technique of color wheel masking. In this way, you retain the properties of the different color relationships, but your choices are restrained to those colors which have inherent harmony due to the way they have been mixed (in terms of pigments, in his case). Otherwise, it can help to create your own palette of a full range of colors that have some overarching tone or tint to them, and then pick your color compositions from those. Really, this might be a little overkill for most projects, but you should use the same idea in order to create and tweak the colors you do use as you go along. Many pixel artists create color ramps with adjoining swatches (sometimes referred to as versatile interpolators or neutralizers), often at the poles or in their neutrals, which force you to use relative color in order to make the color progressions logical and appealing in your work.
It doesn’t matter how you get your end result as long as you're being smart about your color choices and not thinking in terms of visual symbology—the sky isn’t always blue, the grass isn’t always green, etc. This symbolic thinking is very easy to fall into, even when you're not a beginner and you should know better, not just in terms of color but in every aspect of artistic creation. If in doubt, loosen up, experiment. Sometimes happy accidents really are the best way to get yourself thinking about what you see and not what you think you should see.