The VMC200L is a unique 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. Vixen's VMC200L’s primary mirror is f/2.5; the compound optical system is f/9.75. This combination creates a very compact and portable system.
Placing the optical correction placed before the secondary mirror avoids the necessity of having a corrector plate and the dewing problems associated with a closed optical tube. The rack and pinion focusing 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.
The GPD2 equatorial mount is the stronger and heftier of the GP mounts. With its solid steel R. A. and Declination axes and brass worm gears, this mount will hold up to years of heavy use. In order to assure accurate tracking for astrophotography, the worm gears are precisely machined to a very to minimizes periodic error. The VMC200L with GPD2 Mount has been nominated for an Optics Planet Brilliance Award. Vote Now!
|