Colour is an amazing thing.

Your eyes can see a fantastic range of colours – go into a DIY shop or an art shop and just look at how many different coloured paints there are!

Image credit: Christina Rumpf on

Image credit: David Pisnoy on Unsplash

Most of us can distinguish between a million different colours! Some people – who we wrongly call ‘colour blind’ can’t see as many colours, but they can still see thousands. And very rare people can see colours that most of us can’t! One woman can see over 100 million colours!

Did You Know? The correct term for those who can’t see all colours is ‘colour vision deficiency’.

Image credit: Photo by cottonbro from Pexels

How we see colours also depends on what we are looking at and how much light there is.

Colours seem to change if they are on dark or light backgrounds.

Believe it or not, the two squares marked A and B in this picture are the same colour!

Image credit: Thomas Schoch, CC BY-SA 3.0

Optical illusion proof:

See the added rectangle, which is actually the same colour in all parts of the rectangle.

And because of a thing called ‘Colour Constancy’ our brains will sometimes make us see the colours we expect to see! For example – it can make you see red strawberries when they are actually grey!


Walls of Colour. Get a piece of paper and draw a brick wall on it. Or print this handy graphic.


Now pick three different colour paints.

Using these paints, try to make as many different colours as you can so that every brick is different. But even though they are all different they will look ‘right’ side by side because they’ve all been made from the same colours mixed together.

If you also use black and white paints to lighten and darken your mixes you can now create even more different colours. See how many different walls you can come up with!

You can go to the previous PostcardsFromArt secret pages by clicking the places below.

MaterialsWhat is Art?Good or bad art