How does a Maksutov-Cassegrain (MAK) telescope work?

The Maksutov-Cassegrain (MAK) design is a catadioptric design (using both a lens and mirrors) with advantages and disadvantages similar to those of its close relative, the Schmidt-Cassegrain telescope (SCT). It uses a thick meniscus correcting lens with a strong curvature and a secondary mirror that is usually an aluminized spot on the corrector. The MAK optical design typically is easier to make but requires more material for the corrector lens than the SCT.

The Maksutov secondary mirror is usually smaller than the SCT secondary, giving it slightly better resolution for planetary observing. A Maksutov is heavier than an  SCT of the same aperture, and because of the thick correcting lens, it takes a long time to reach thermal stability at night.

Updated 11/5/13