The VMC200L is a unique 200mm 8 inch
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 nto 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.
| Specifications: |
|
| Construction: |
|
Catadioptrical reflector |
|
d=200mm (8”) ; f=1950mm, f/9.75 |
| Primary mirror |
f=1950mm, f/2.5 |
| Secondary mirror: |
d=72mm, magnification 3.9x |
| Distance primary secondary |
~330mm |
| Central obstruction |
80mm diameter (40% of d |
| Theoretical resolution (Dawes): |
0.63" |
| Theoretical min mag: |
13.3 |
| Tube length |
~525mm incl. focuser |
| Weight: |
5.9kg (13 lbs) |
| Dimensions: |
232mm x 535mm (9.1 x 21 inches) |
| Finder scope: |
7x50 (Item 2633 only) |
