The Cassegrain Reflecting Telescope
A Cassegrain telescope uses mirrors to reflect light from a primary concave mirror to a reflecting secondary convex mirror, then back through a hole in the centre of the primary mirror to an eyepiece where it is brought to a focus.
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The Cassegrain has the advantage over a Newtonian by having a large f-number (ratio of focal length to primary mirror diameter), allows much magnification, and the design means the Cassegrain reflector is more compact, allowing a more powerful telescope in the same length of tube. You have no rights to post comments