Colour constancy

We never see what we appear to be seeing. The white that we appear to be seeing isn’t white. The one red colour we appear to be seeing is in fact a collection of very differing colours: from dark violet in the shade to bright orange in the sun. Take a good look at the picture and convince yourself.
But there’s a lot more to it. If, after a while, we look at the same building again, we’d swear the colours didn’t change. After all, nobody painted the building in the meantime. This, however, is a misconception.

The same building doesn’t look quite the same at another point in time. The fact that we appear to see the same colours is the result of a very powerful psychological phenomenon that is called ‘colour constancy’. Colour constancy is a subconscious colour correction that all humans have, which enables us to maintain the illusion that Coca-cola red is always Coca-cola red.

next page