VC200L
Telescope
Vixen VC200L
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
200mm/7.9” @ f/9
Advanced Photo / Visual
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-and-
pinion focusing mount accepts optional 2”
eyepieces and accessories, and an f/6.4
reducer for photographic use is available.
VISAC Solves Aberration
Of the common catadioptric telescopes, only the VISAC
system solves spherical, coma and curvature of field.
Curvature
of Field
Reviews
Telescope Types Spherical
Coma
“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-the-
telescope photography.”
Classical Cassegrain
Dall-Kirkham
Corrected
Corrected
Corrected
Corrected
L L
L L
Ritchy-Chretien
Schmidt-Cassegrain
V I S A C
Corrected
L
L L
Corrected Corrected Corrected
— 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.”
VC200L Telescope Schematic Drawing
Note special 3-element corrector in focus tube
of this unique catadioptric design.
— Scopereviews.com, 12/16/2003
Copyright © 2002-2004 Vixen North America, 32 Elkay Dr., Chester, NY 10918. All rights reserved.
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