colour perception Tag

Our eyes can be easily deceived when we view colour, and understanding the limitations of colour perception helps achieve clear expectations for colour accuracy. The deception is mostly due to our brain, which is processing a ton of information and doing the best it can. Some factors like genetics play a part, but so does the environment. The light in the environment is the biggest factor on how we perceive colour.

This post is a quick introduction to the different ways our perception of colour can be effected. This post is a summary – for a more in-depth look, please reference X-Rite’s Colour Perception Blog Series, the main source of this post.

Temperature of Light

The human eye can view millions of colours, but it breaks down to three primary colours: red, green, and blue.

RGB is the foundation of human colour vision.

It’s important to understand that objects don’t actually have a colour. They have properties that determine how light is absorbed and reflected. The mix of that reflected light is what our eyeball uses to perceive the colour.

This example of a red car under different light shows how our perception of colour can change when the ambient light changes. When the same colour is viewed under different light sources it can appear quite differently. Typically more blue under a night sky, or more yellow under a fluorescent light.

Our brains have learned that objects should look a certain way, so sometimes our brain applies this logic in interesting ways that can change our perception of colour.

The optical illusion below from Beau Lotto shows it really well. Once the rest of the colours on the cube are masked you can see how much they effect your perception of colour.

Optical Illusion images courtesy of R. Beau Lotto.

This is all very important to understand when colour communication is critical.

Reflectiveness and Texture

Since the colours an object absorbs and reflect have such a big effect on colour perception, the material of the object itself becomes important in the way the colour is perceived.

This can be a challenge in the manufacturing and print industries. Most print shops (including ours) will use bright ‘Day Light’ tuned bulbs to help ensure that colours are being viewed accurately, and to avoid common optical illusions.

Technology can be a roadblock to communicating colour, as well. One of the biggest challenges is between different displays on electronic devices. We view colour many ways: on our phones, TV, computer screens, in print, on a tablet, etc. The brightness and other variables will all change the way a colour is perceived.

The Environment and Fatigue

The environment that the colour is viewed in has a large effect on perception, but once that light passes through the eye there are other variables that can change the way a colour is perceived.

Retinal fatigue can contribute to colour perception issues. Just like the rest of our body, the eye benefits from rest, and is affected negatively by fatigue.

Use the example below from to experience retinal fatigue. If you stare at this image for around 30 seconds and then close your eyes, you will see a shadow of the image on the back of your eyelids. This ‘afterimage’ occurs because when we stare at an object the chemicals in our eye’s cones start to deplete and send incorrect information to our brain. Your eyes will adjust and reset shortly, but this is a good example of how quickly an eye can become fatigued and alter colour perception.

Background effects can play a role, as well. In the example below, are the arrows the same colour?

They really are. Each background colour strongly changes our eye’s ability to perceive colour.

So while light plays a big role, we need to remember that our eyes can be tricked. A tired eye cannot make great judgments. Surrounding colours and light in the environment can trick your eye and cloud your view.

Human Traits

Last but not least are our human traits. The human eye and brain has several limitations, and some people are better able to detect slight changes in colour. Curious about your colour deficiency? There’s a test at the end!

True colour blindness where a person sees only grey is apparently quite rare. We only use Red, Green, and Blue to perceive colour though, so any slight change in those chemical sensors will change the way we perceive light.

Do you see a 6, and a 2? If not, you may be experiencing a colour deficiency.

Age, poor colour memory, and life factors like stress can all play a role in your chemical reaction to wavelengths of light.

If you’re worried or curious about colour deficiency, the easiest thing to do is take a test!

X-Rite has a FM100 Hue Test available to do a quick check of your colour perception. There’s another version here, too. How did you do? Let us know!