Colour Theory

This page has info about the science and history behind colour theory and also info about colour models.

Light Spectrum

rainbows

It was Issac Newton who first figured out some of the true nature of light from his experiments in the late 1600’s.

A Cautionary Tale About Rainbows

Colour Vision

We humans are capable of seeing all the colours of the rainbow thanks to our eyes and brains working together. Some of it is an illusion. Most Interesting Fact: The colour purple isn’t “real”. It’s a figment of our imaginations. It’s all explained very nicely in the Craig Blackwell videos.

Craig Blackwell has an excellent series about colour vision on YouTube.

Craig Blackwell
Color Vision 1: Color Basics
Color Vision 2: Color Matching
Color Vision 3: Color Map
Color Vision 4: Cones and the Opponent Process
Color Vision 5: Cones to Color – Opponent Processing
Super Vision
a person who can see MORE colors than the rest of us thanks to having 4 types of retinal cone cell insta of three

Cyan-Magenta-Yellow: An Alternative To Red-Yellow-Blue

By the time we are young kids, most of us have already learned about the Red-Yellow-Blue (RYB) colour model

It wasn’t until much later in life that I learned about the Cyan-Magenta-Yellow (CMY) colour model.

CMY replaces the primary colours, blue and red, with new primaries, cyan and magenta. Using this model, blue and red become secondary colours instead of primary.

When I first learned about the CMY colour model, I thought “why bother?” At first, I thought CMY and RYB were equivalent. I thought both models could make the same range of colours if you mixed things right.

After doing further research, I realized that conclusion about colour was wrong. The CMY colour model is capable of producing a wider range of painted colors.

After doing some experimenting with the IMageKiink dollar store cyan and magenta, I’m finding I get quite good results.

How CMY Works

Why is this? Here’s what I think is the primary reason. See what I did there?

One rule with mixing paint/pigments is that mixing two colours always produces a darker color. Now compare cyan with blue and compare magenta with red. You will see that cyan is lighter than blue, yet it is still a fully saturated color. You will also see that magenta is lighter than red, and it is also fully saturated.

The fact that those colours are lighter yet still fully saturated is the reason why you can make a wider range of colors. Using CMY, you can mix a darker blue or red. However, using RYB, you cannot properly mix a fully saturated lighter hue of blue or red to make cyan or magenta.

Suppose you are starting with a darker blue or a darker red, and you want to get a lighter one without desaturating it by adding white. The only way to make a colour lighter is to add white, but that unavoidably causes some desaturation of the color.

How do you get around that? First, you begin with a lighter, fully saturated, version of blue. That’s what cyan is. Next, you use a lighter, fully saturated, version of red. That’s magenta. You can’t get fully saturated versions of either of those colours by adding white to blue or red.

My understanding is that CMY is almost the equivalent of RYB except that it uses lighter, yet fully saturated, versions of red and blue.

Painting With CMY On A Budget

So which colour model will I use for my paintings? I guess that will depend on what sort of colours I want to achieve and also on the cost and availability of those particular pigments. Some pigments are more expensive than others. If it looked like cyan and magenta were going to be too pricey, I would opt for blue and red!

One thing is for sure: you’re not likely to find Cerulean Blue or Quinacridone Rose at a dollar store. While the CMY colour palette might work well, it is not for artists on a budget. If cost is a factor for you, I would suggest sticking with the traditional RYB colour model.

Since CMY is often more expensive and less familiar to most people, I will usually refer to RYB in my instructions.

Make Your Own Magenta and Cyan

After many experiments, I think I’ve finally made a good cyan and magenta using dollar store ingredients. You can make cyan and magenta using the “neon” paints from a dollar store. These are fluorescent acrylics that are displayed in the same spot in the store as the other acrylic paints. The neon colours are a good base since they are relatively light, yet still vibrant and saturated.

In both cases, some white may be required to match a colour wheel, but you’ll get better mixing results if you don’t use any white. Use as little white as possible.

In the case of magenta, it looks much darker under dim lighting. However, under sunlight or bright cool LED light, it is a perfect match to a CMY colour wheel.

IMageKink Cyan

In the case of cyan, some white is required in order to get it to match a CMY colour wheel. However, adding white interferes with mixing colours. Use as little white as you can get away with.

Colour Amount
Neon Blue 15.0 ml
Neon Yellow 0.25ml
White (optional) 0 – 0.75 ml
IMageKink Magenta

In the case of magenta, I found no white was required in order to get it to match a CMY colour wheel. However, you may wish to add a small amount.

Colour Amount
Neon Pink 15.0 ml
Neon Blue 1.5ml
White (optional) 0 – 0.25 ml