Product Description
This 24" long aluminum Celestron 11" Schmidt Cassegrain optical tube weighs only 27.5 lbs., making it easy to transport. It has an 11" aperture, a 2800mm focal length, and a focal ratio of f/10. An optional focal reducer is available to bring the focal ratio down to f/6.3 for CCD and 35mm photography. Optical performance is guaranteed to be diffraction-limited.
Advanced high transmission Starbright XLT optical multicoatings are standard equipment. This coatings package includes high reflectivity multilayer aluminum mirrors enhanced with titanium dioxide for high reflectivity, plus a unique combination of magnesium fluoride and hafnium dioxide antireflection coatings on both sides of the Schmidt corrector lens. The corrector lens itself is made of high transmission water white float glass instead of conventional soda lime glass (which has 3.5% lower transmission) used in other telescopes.
Starbright XLT multicoatings visibly increase the contrast on subtle lunar, planetary, and nebula details when compared with a scope with standard multicoatings. They also give you higher light transmission for brighter deep space images and shorter exposure times during CCD and 35mm photography. Across the total visual/photographic spectrum from 400nm to 750nm, independent laboratory tests show the new Starbright XLT coatings are 16% brighter overall than even the original industry-standard Starbright multicoatings.
The optical tube comes with a big 9 x 50mm straight-through achromatic finderscope and mounting bracket. The finder has a wide 5° field of view. It focuses by loosening the trim ring behind the objective lens cell, screwing the lens cell in or out to focus, and tightening the trim ring to lock in the correct focus. Also standard is a removable 1.25" visual back that holds visual accessories such as a star diagonal, tele-extender, etc. A 1.25" prism type star diagonal is also standard, as is a 1.25" 40mm Plössl eyepiece. This eyepiece provides a magnification of 70x. Its field of view is 0.68° across, over a third wider than the full moon. Dust covers for the optics are also supplied.
The optical tube is equipped with a slide bar with a standard 75mm (3") wide dovetail for mounting the tube on Losmandy Style saddles.
Tech Details
| Aperture | 11" |
|---|---|
| Focal Length | 2800mm |
| Focal Ratio | f/10 |
| Heaviest Single Component | 27.5 lbs. |
| Highest Useful Magnification | 560x |
| Weight | 27.5 lbs. |
| Optical Coatings | StarBright/XLT |
| Resolution | 0.41 arc seconds |
| Telescope Type | Schmidt-Cassegrain |
| Visual Limiting Magnitude | 14.7 |
| Warranty | 2 years |
Reviews
Image quality is very good, it almost doesn't have backfocus problems, you can accomodate almost any imaging equipment with this OTA.
Visually it is a very powerful OTA, and fitted with binoviewers planet watching is breath taking, specially Saturn.
Very good all around Telescope.
Clear skies
Javier. (Posted on 8/4/2017)
There is significant mirror shift when using the focusing knob, so factor in an upgrade to a moonlight or SCT crayford focuser which will add about 3lbs to the weight.
Due to it's aperture, this is very sensative to precise collimation, but star tests very well when seeing is stable. (Posted on 8/4/2017)
Supplied Accessories
- Starbright XLT multicoated optics
- 40mm 1.25" Plössl eyepiece (70x)
- 1.25" visual back
- 1.25" prism-type star diagonal
- 9 x 50mm straight-through finderscope
- Dust covers
- Dovetail for mounting on Celestron CGE and Losmandy G-11 and HGM Titan mounts