Cycloid

Mikołaj Thanks! I remembered learning about the cycloid in a Calculus class as a freshman. I've wanted to try this since I got into photography and finally did it last year. Can you try to think of other mathematical shapes one can photograph using long exposure and everyday objects?

Marcin K. Concentric arcs of stars movement

Marcin K. If you have a ball that gives some light:
Parabolic shape by throwing

Marcin K. Conic sections by using e.g. a flash light or a lamp with a proper shade