Striking a comfortable balance between power and portability, the Celestron C8-A-XLT CGE 8" f/10 Schmidt-Cassegrain Telescope is an ideal choice for observing objects within or beyond our solar system. It features a Schmidt-Cassegrain optical system consisting of a corrector plate, a spherical primary mirror, and a secondary mirror that work together to reduce spherical and chromatic aberrations. These corrections result in crisp and clear high-resolution images with accurate color representation, without distortion—especially at the edges. Complementing the optical system is the proprietary StarBright XLT optical coating system, which improves light transmission and reflectivity across the entire visual spectrum.
The optical tube is outfitted with a standard 1.25" visual back to make it easier to find eyepieces, accessories, and imaging gear. For visual observations, a 1.25" star diagonal is included along with a 25mm eyepiece that yields 81x magnification. The C8-A-XLT is offered here without a mount or tripod for users who already have a reliable support system and are looking to upgrade or add to their existing gear, but comes with a larger CGE dovetail plate that is compatible with Losmandy-style saddles.
- 8" (203mm) aperture
- f/10 focal ratio
- 2032mm effective focal length
- Schmidt-Cassegrain catadioptric optical design
- StarBright XLT optical coatings
- Resolution: 0.69 arcsec (Rayleigh); 0.57 arcsec (Dawes)
- Secondary mirror obstruction: 2.5" (69mm); 31% by diameter; 9.77% by area
- Maximizes light transmission through optical path
- Improves color rendition, contrast, sharpness, resolution, and brightness
- Broadband system provides flat wavelength transmission across the entire visual spectrum
- Multi-layer mirror coatings with layers of aluminum, SiO2 (quartz), and TiO2 (titanium dioxide)
- Multi-layer anti-reflective corrector plate coatings with layers of MgF2 (magnesium fluoride) and HfO2 (hafnium dioxide); hafnium has a wider band-pass than the commonly used titanium
- High-transmission water white glass corrector plate limits light loss due to internal absorption
- optical tube assembly (OTA) only; mount and tripod required for proper use
- CGE (Losmandy-style) dovetail plate for compatible saddles
- OTA weight: 12.5 pounds
- Visual back:
- Standard Schmidt-Cassegrain telescope threads
- 1.25" eyepiece/accessory holder
- Use for prime focus or projection astrophotography with optional adapters
- Eyepiece:
- 1.25"-diameter barrel
- Accepts most 1.25" eyepiece filters
- 25mm focal length yields 81x power
- Diagonal:
- 90° angle puts head in comfortable viewing position
- Threaded for direct connection to OTA without the need for the visual back
- 1.25" snout and eyepiece/accessory holder
- Star diagonal corrects image horizontally, but not vertically
- Finderscope:
- Low 6x magnification preserves wide field of view to more easily find alignment or guide stars
- 30mm aperture helps to see dimmer objects and stars for easier alignment and star-hopping navigation