M.C. Escher: Adventures in Perception (1971) is a 20-minute Dutch documentary about the artist and includes scenes of him working in his studio. From Open Culture:
Obsessed with perspective, geometry, and pattern (Escher described tessellation as "a real mania to which I have become addicted"), his images have, by the count of mathematician and Escher scholar Doris Schattschneider, led so far to eleven separate strands of mathematical and scientific research.
The twenty-minute Adventures in Perception, originally commissioned by the Netherlands' Ministry of Foreign Affairs, offers in its first half a meditation on the mesmerizing, often impossible world Escher had created with his art to date. Its second half captures Escher in the last years of his life, still at work in his Laren, North Holland studio. It even shows him printing one of the three titular serpents, threaded through a set of elaborately interlocking circles, of his very last print Snakes. He never actually finished Snakes, whose patterns would have continued on to the effect of infinity, and even says here of his officially complete works that none succeed, "because it's the dream I tried for that can't be realized."