Klevtsov-Cassegrain
This design is based on the Maksutov-Cassegrain. It provides correction of aberrations via a two element meniscus-shaped corrector lens in front of the secondary mirror. This design was originally envisaged by G. I. Popov with a practical implementation by Yu. A. Klevtsov. It is produced with apertures of 8, 10.25 and 13 inches. The 8 inch model employs a refractor style rack and pinion focuser while in the larger designs the primary mirror is moved as in most other small to medium sized Cassegrain designs.
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