Assessments - 4, GPA: 4.3
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With its unique VISAC (Vixen Sixth-Order Aspheric Cassegrain) primary mirror, the optical system is composed of a concave primary mirror, a convex secondary mirror and a three-element field corrector. Especially noteworthy is its sharpness and flatness at the edge, which far exceeds that of Schmidt- Cassegrain systems of the same aperture. It provides a pinpoint star image of less than 15 microns, even at the edge of its 42mm image circle. The open tube design eliminates the dew problem that is common with conventional Schmidt-Cassegrain systems and its size makes it very easy to handle. · The VC200L is well suited for observation and astrophotography of the moon, planets, star clusters, nebulae and comets. The rack-andpinion focusing mount accepts optional 2” eyepieces and accessories, and an f/6.4 reducer for photographic use is available. Reviews “Owners comment that the VC200L yields flat, distortion-free images from edge to edge thanks to the corrector lens, while spherical aberration is minimized thanks to the aspheric primary mirror. The result is pinpoint stars from edge to edge, an important consideration for through-thetelescope photography.” — Star Ware, 3rd edition, pg.146 “[C]atadioptric fans should take a close look at this scope, since it does offer a few advantages compared to your standard issue Schmidt- Cassegrain. … . The build quality is much better than most mass-produced SCTs. The Vixen has a 2" rack and pinion focuser, which eliminates the primary image shift in an SCT. Also, the scope is collimatable to an impressive degree … . Finally, there's no corrector plate to collect dew.” — Scopereviews.com, 12/16/2003 VC200L Telescope Schematic Drawing Note special 3-element corrector in focus tube of this unique catadioptric design. VISAC Solves Aberration Of the common catadioptric telescopes, only the VISAC system solves spherical, coma and curvature of field. Telescope Types Spherical Coma Curvature of Field Classical Cassegrain Corrected LL Dall-Kirkham Corrected L L Ritchy-Chretien Corrected Corrected L Schmidt-Cassegrain Corrected LL V I S A C Corrected Corrected Corrected Vixen VC200L 200mm/7.9” @ f/9 Advanced Photo / Visual VC200L Telescope Design · The VC200L’s catadioptric optical system is one of the most sophisticated optical designs available on the market today. With its unique VISAC (Vixen Sixth-Order Aspheric Cassegrain) primary mirror, the optical system is composed of a concave primary mirror, a convex secondary mirror and a three-element field corrector. Especially noteworthy is its sharpness and flatness at the edge, which far exceeds that of Schmidt- Cassegrain systems of the same aperture. It provides a pinpoint star image of less than 15 microns, even at the edge of its 42mm image circle. The open tube design eliminates the dew problem that is common with conventional Schmidt-Cassegrain systems and its size makes it very easy to handle. · The VC200L is well suited for observation and astrophotography of the moon, planets, star clusters, nebulae and comets. The rack-andpinion focusing mount accepts optional 2” eyepieces and accessories, and an f/6.4 reducer for photographic use is available. Reviews “Owners comment that the VC200L yields flat, distortion-free images from edge to edge thanks to the corrector lens, while spherical aberration is minimized thanks to the aspheric primary mirror. The result is pinpoint stars from edge to edge, an important consideration for through-thetelescope photography.” — Star Ware, 3rd edition, pg.146 “[C]atadioptric fans should take a close look at this scope, since it does offer a few advantages compared to your standard issue Schmidt- Cassegrain. … . The build quality is much better than most mass-produced SCTs. The Vixen has a 2" rack and pinion focuser, which eliminates the primary image shift in an SCT. Also, the scope is collimatable to an impressive degree … . Finally, there's no corrector plate to collect dew.” — Scopereviews.com, 12/16/2003 VC200L Telescope Schematic Drawing Note special 3-element corrector in focus tube of this unique catadioptric design. VISAC Solves Aberration Of the common catadioptric telescopes, only the VISAC system solves spherical, coma and curvature of field. Telescope Types Spherical Coma Curvature of Field Classical Cassegrain Corrected LL Dall-Kirkham Corrected L L Ritchy-Chretien Corrected Corrected L Schmidt-Cassegrain Corrected LL V I S A C Corrected Corrected Corrected Vixen VC200L 200mm/7.9” @ f/9 Advanced Photo / Visual Visit or call us Mon. - Fri. from 9 a.m. -5 p.m. ET: 845 469 8660 Copyright © 2002-2004 Vixen North America, 32 Elkay Dr., Chester, NY 10918. All rights reserved. ...