Celestron NexStar 8 GPS Schmidt-Cassegrain Telescope is part of Celestron's "top of the line" fork-mounted astronomical telescopes. 8GPS Celestron NexStar Telescope is at home as a superb visual instrument or, with optional CCD cameras, as a serious scientific research tool.
Besides seeing all of the Messier Catalog objects, you can also see hundreds of other, less famous, but equally interesting NGC, IC and Caldwell objects. Turn NexStar 8 GPS Telescope to the planets and see amazing detail on the surface of Jupiter; see Cassini's Division in the rings of Saturn, and resolve details on the surface of Mars. Even the distant Uranus, Neptune and Pluto are within your reach.
Although large in aperture, with its conveniently located carrying handles and an instrument weight of only 42 pounds, the Celestron 8 GPS Telescope is portable enough to set up in your backyard or take with you to your favorite dark sky location.
With StarBright XLT Optical system design you'll see the light. One of the most important factors in the evaluation of a Schmidt-Cassegrain telescope 's 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 StarBrightXLT high transmission optical system design:
- 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.
- Multi-layer anti-reflective coatings: 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.
- 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.