A former colleague even made an airbrush in which the inside of such a form was darker than the environment, and still, it seemed lighter.
So I wanted to examine that. How much black can I add until the inner shape seems darker than the outer space?
It turns out that there may be around 5 to 8% black added to the white before the effect is eliminated. Pretty much, isn’t it? It’s way more than I expected.
And in the example below you can also see how much influence colours and shades have on each other. The shape on the right side is the tint I used in the inner circle!
An optical illusion: the grey of Adelson
Another great example is at the bottom of this article. I found it hard to believe my eyes, but the proof is laid out in the video.
Do you know other optical illusions that are remarkable? Tell me in the comment box below.