Reflectors

400mm f/20 Classic Cassegrain on collimation bench

Collimating a 400mm f/20 Classic Cassegrain

Reflectors

Collimating a Classic Cassegrain telescope – or any telescope with more than one curved mirror – is not easy. Catalin from CFF Telescopes collimated this 400mm f/20 with an artificial star, a beam splitter and an optically flat mirror.

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