In catadioptric telescopes, focusing is achieved by moving the primary mirror back and forth. When changing direction, the mirror may tilt slightly, making precise focusing more difficult. The TS-Optics 1:10 Monorail focuser for SC telescopes provides a solution to this problem, effectively replacing the mirror-moving focusing mechanism with a precise, fine-adjustment system similar to the Crayford focusers commonly used on refractor telescopes, but with greater load capacity.
The Monorail system provides stronger and more precise adjustment than the Crayford system, as it uses a solid stainless steel rail instead of small ball bearings. The ball bearings are only responsible for lateral guidance. These bearings merely maintain the lateral position and no longer need to support the load, as the steel rail carries it.
The focuser accepts 2" eyepieces, while the included 2"-1.25" adapter allows the use of smaller 1.25" eyepieces as well. The focuser is primarily designed for Schmidt-Cassegrain telescopes, but it can also be fitted to Maksutov-Cassegrain telescopes with an optional SC-MC adapter.
