Introduction to astrolabes: history, design and how they work.

Ancient astrolabes are genuine pieces of art and clever astronomical calculators. This presentation will introduce mariner’s astrolabes and other types, and will explain in details how a planispheric astrolabe is built and how it works. Many drawings are taken from Shadows Pro, a shareware software that can precisely draw and animate astrolabes.
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And here’s a guy who has built one!