The Maksutov or ‘Mak’ is a catadioptric telescope design that employs a full diameter positive meniscus lens (commonly called a “corrector plate”) to correct the problems of off-axis aberrations such as coma found in reflector telescopes while also correcting chromatic aberration. The design is most commonly seen in a Cassegrain variation, with an integrated secondary, that can use all-spherical elements, thereby simplifying fabrication. The chief disadvantage of the design is that it does not scale up well to large apertures (>250 mm/10 inches), since the corrector plate rapidly becomes prohibitively large, heavy and expensive as the aperture increases most commercial manufacturers usually stop at 180 mm (7 inches).
The focal ratio of the Maksutov-Cassegrain design provides high powers and a narrower field of view. This makes them unsuitable for wide-field astrophotography but superb at lunar and planetary imaging. They are also very adept at imaging tightly packed formations such as globular clusters and at splitting double stars.