One of the presentations at this year’s Gathering 4 Gardner event was about optical illusions, a favorite topic of mine. The presenter, Chris Robeson, showed some pictures of an art exhibit called “Squaring the Circle” by Eva Rucki’s collaborative art group, Troika. The exhibit takes up the better part of a room and is intended mainly for museums I suppose.
By using parallax distortion the exhibit looks like a square from one viewpoint and like a circle from another. I thought the math to recreate the illusion would be pretty straightforward and there’s nothing about the illusion that requires a whole room so I’ve made one that you can hold in your hand. Et voilà:
From the side it looks like Sauron’s tower or something but the illusion kicks in when you look along its length:
From one end, it looks like a square surrounding a circle but from the other, it looks like a circle surrounding a square. Here’s a video demonstrating the effect. It’s fun to have someone stand a few feet away and have both of you sight along its length so that one person’s description of what they’re seeing is the opposite of the other’s.
I’ve made a dozen and they’re available at my Etsy store if you’re interested. (By the way, in case you’re wondering, “squirclusion” is a portmanteau word from SQUare cIRCle ilLUSION.)