At the end of October 2022, Svbony announced the release of a mirror-lens telescope of the Maksutov-Cassegrain system with an aperture of 105 mm. This was quite unexpected, since before that among Svbony telescopes there were only lens telescopes (refractors). And so, Svbony kindly provided me with a MK105 telescope for testing.
The meniscus optical system was invented by the Soviet scientist and optician Dmitry Dmitrievich Maksutov in 1941. In the Maksutov-Cassegrain system, the primary mirror is a spherical high-aperture mirror. Spherical aberration of the primary and secondary mirrors is compensated for with a full aperture lens corrector (meniscus) at the front of the tube. In this case, a convex spherical secondary mirror can be deposited directly on the meniscus, but then the relative aperture of the telescope should be in the range of 1:12–1:15 to eliminate spherical aberration as much as possible. For the first time I looked into the meniscus telescope around 2007 and since then I have fallen in love with the “poppies” for their compactness, the complete absence of chromatism, the absence of rays in the image and unpretentious maintenance. However, despite the apparent simplicity (all optical surfaces can be spherical!), increased requirements are imposed on the mechanics, mirrors, and especially the meniscus, otherwise the telescope will not be able to provide alignment stability and diffraction image quality. ЧИТАТЬ ДАЛЕЕ (READ MORE) > > >