Did you solve it? You won’t believe these optical illusions!

Earlier today I posted five optical illusions by Olivier Redon, a French-American inventor. Here they are again — with demonstrations of how he created the effects. Three of the images are inspired by the Necker cube, a two-dimensional drawing of a cube that can be understood in two ways: either with the bottom left face at the front, or the top right face at the front.

Once your eyes settle on one interpretation, it is hard to see the other. Ceci n’est pas une canette appears to be the outside of a complete can but is actually an inverted internal segment with the top stuck on upside down; the two pieces you need are the top disc and the side section.

The Oh La La Box is not a red box but two pieces of cardboard arranged in an X shape, another Necker-style trick that a video makes hard to believe. Twin dinos are the same size in the picture thanks to lines of perspective created by photographing the figures at horizontal and vertical angles.

optical illusions, olivier redon, necker cube, necker-style, cardboard, twin dinos, perspective lines, top disc, side section, video demonstration