Pop Colors Spiral Illusion


Look carefully at the image below. Do you see a couple of spirals, one blue and one green? Well, take a closer look – in actual fact, the blue and green are actually the same color.

Monspiral

Don’t believe it ? Copy the image and open it up in PhotoShop or Paint and take a closer look….
You will notice that the orange curves move through the “green” spirals, but not the blue. And the purple curves don’t move through the green.

monspiral4

If we blow this picture up even more, we can see that the colours are becoming more and more similar.

monspiral5

The blue and green appear to be different colours because our brain works out colours by comparing them to other surrounding colours and it does a bit of mixing. When we look at the “blue” spiral, we also take in the purple curves moving through it. This makes it look more blue. When we look at the “green” spiral, we take in the orange curves, which makes it look more green.

I know that’s not a great explanation, so I’d be happy to hear a better one!

Edit by westius 2/7/09: If you doubt this illusion, check out this image – I’ve replaced some of the colours – you can clearly see now that the ‘blue’ and ‘green’ are the same:

colour_replaced