Impossible Exploration

Objective: Explore impossible objects in Escher's work.

1. Try this Animated Necker cube applet by Mark Newbold.
2. What’s wrong with Waterfall (Magic of M.C. Escher #195)?
3. What’s wrong with Ascending and Descending (Magic of M.C. Escher #242)?
4. Belvedere (Magic of M.C. Escher #235) contains many impossibilities. Describe as many as you can.
5. What's going on in Convex and Concave (Magic of M.C. Escher #201)? What depth cues are ambiguous here? The picture has two parts which are perfectly fine by themselves, but which disagree when combined. Where are the two parts?
6. Explore the Impossible Worlds website to see many more impossible figures by other artists, especially work by Oskar Reutersvärd.

Handin: A sheet with answers to all questions.