The VMC200L Reflector Telescope is a unique 200mm, 8" catadioptric optical system. It incorporates a primary mirror and a meniscus corrector just before a secondary mirror. By doing so, light is corrected twice on the optical path. The end result is that spherical aberration and field curvature are corrected to a high degree of optical performance. The VMC200L’s primary mirror is f/2.5; the compound optical system is f/9.75. This makes the system much more compact and portable than its competition.With the optical correction placed before the secondary mirror, the VMC200L avoids the necessity of having a corrector plate and all the dewing problems associated with a closed optical tube
An additional key feature is the rack and pinion focusing that is placed behind the primary mirror. The use of this focusing system eliminates the image shift associated with most other SCT systems. This is especially important when using high power magnification or astro-photography. When focusing, the image is stable and easy to adjust. Astronomy Technology> says "the f/9.75 focal ratio is noticeably faster than the typical Maksutov design .which translates into a wider true field of view. Reaching focus is easy...Lightweight, portable, 8 inches of aperture, fast cool down, zero image shift, and reasonably priced - I guess it may be possible to have your cake and eat it too."