Dvor is a new marketplace by OpticsPlanet with the latest and greatest gear at unbelievable prices. We're talking high quality brand name merchandise at low, low prices on shooting, outdoors, sports gear and so much more. Exclusive membership, exclusive deals, but limited time, limited quantities: this is what Dvor is all about. Learn more at Dvor.com!
Please note that Celestron C11 S XLT Telescope w/ StarBright XLT Coatings 11066-XLT has been replaced with Celestron C 11 SGT XLT Telescope w/ StarBright XLT Coatings 11067-XLT
With StarBright XLT Optical System you'll see the light!
One of the most important factors in the evaluation of a Schmidt-Cassegrain
Telescopes Optical System performance is its transmission " the percentage of incoming light that reaches the focal plane. The design of the XLT System accomplishes two crucial objectives: Develop a coating system that is optimized for visual use and for CCD/Photographic imaging.
There are three major components that make up Celestron
Star Bright XLT high transmission optical system design:
1. Unique enhanced multi-layer mirror coatings:
Celestron
mirror coatings are made from precise layers of Al (Aluminum), SiO2 (quartz) and TiO2 (Titanium Dioxide). Reflectivity is fairly flat across the spectrum, optimizing it for both CCD imaging and visual use.
2. Multi-layer anti-reflective coatings:
Celestron
Star Bright XLT
Coatings are made from precise layers of MgF2 (Magnesium Fluoride), and HfO2 (Hafnium Dioxide). Hafnium gives a wider band pass than Titanium, used in comparable coatings.
3. High Transmission Water White glass :
Celestron Schmidt-Cassegrain Optical Systems with optional StarBright XLT coatings use Water White glass instead of Soda Lime glass for the corrector lens. Water White glass transmits about 90.5% of light without anti-reflective coatings. That is 3.5% better transmission than uncoated Soda Lime glass. When Water White glass is used in conjunction with StarBright - XLT 's anti-reflective coatings, the average light transmission reaches 97.4% " an 8% improvement!
These three components of Celestron StarBright XLT Coatings result in one of the finest coatings available. The
peak light transmission for the systems is 89% at 520 nm. The overall system
transmission is 83.5% averaged over the spectrum from 400 to 750
nm.
Specifications for Celestron C 11 S Telescopes:
| Optical Design: | 11" (279mm) Schmidt-Cassegrain | |
| Focal Length: | 2800mm | |
| Focal Ratio: | f/10 | |
| Coatings: | StarBright Multi-Coatings | |
| Eyepiece: | 1.25" 40mm E-Lux Eyepiece (70x) | |
| Finderscope: | 9x50 | |
| Tube Color: | Glossy Black | |
| Telescope Weight: | 91 lbs | |
Celestron C11 S Schmidt-Cassegrain Telescope with CG-5 German Equatorial Mount