Your Cart

The colour wheel is wrong

Sateenkaari-emoji läheltä | The rainbow emoji from up-close

🎨 Yesterday I published a reel where I mentioned that the traditional colour wheel used among artists is wrong.

👎 Not completely wrong but, from the point of view of physics, there is a better choice of three base colours.

🔴 Base colours are those colours that cannot be created by mixing any others.

🤔 But wait a minute… how do we create colours?

👁 In our eyes there are receptors which react to red, green or blue light.

🤔 But how do we see the rest of the colours if there isn’t a receptor for, e.g., yellow?

🟢 The receptors which react to red are sensitive to different shades of red and also somewhat sensitive to orange and red. Likewise, the receptors which react best to green can recognise yellow, too.

🖥 This is employed, for example, in displays. There are pixels which consist of three components – red, green and blue. They emit a certain amount of light which combined together are identified by our brain as yellow, orange, violet, etc.

🌈 In this photo you can see the rainbow emoji from very close – I simply took a photo of it with a lens with high magnification. The pixels are so small that usually, our eyes can’t easily discern them, so it appears as if the pixel emits one particular colour.

🔵 Note how in the orange area of the rainbow there are red and dim green lines. In the yellow area the red and the green are equally bright

🤔 Ok but why the base colours aren’t red, yellow and blue?

🟤 Mixing red, yellow and blue gives dark brown. It’s more logical that the choice of base colours is such that it produces black. This is the case when replacing yellow with green.

(Originally posted in Finnish on my Instagram account @valontarinat)