Take a close look at the 12 spheres in the image. Some look green, others reddish, blue, or orange. Even when you compare them side by side, it’s hard to believe they could have anything in common.
But there’s a trick: they all have exactly the same base color.
The image was created by David Novick, a professor of Engineering at the University of Texas at El Paso known for his optical illusions. The trick is the so-called Munker-White effect, which alters our perception of a color depending on the shades surrounding it.
In this case, the stripes running across the spheres make our brains interpret their colors differently. Novick explained that all 12 have the same light brown hue, with RGB values of 255, 188, and 144.
The proof becomes clear when the colored lines are removed: without them, the apparent differences between the spheres disappear.
And there’s a curious way to intensify the illusion. Move away from the screen or shrink the image. When you make it smaller, the stripes and spheres blend together even more visually, and the apparent colors become more intense. If you do the opposite and enlarge the image, the effect starts to weaken.