deke.com posts about optical

Coffer Illusion and the Hidden Circles

Deke hides 16 circles in a way that, once you see it, you'll never unsee.

Deke's Techniques 100: Creating an Dual-Focus Hybrid Image

Learn how to create a specific and famous flavor of optical illusion. When viewed from far away, the image appears as one thing; when viewed close up, it appears as another.