Celestron C8 Optical Tube Assembly (CGE Dovetail)

Celestron C8 Optical Tube Assembly (CGE Dovetail)

The Celestron C8-A is the evolved successor of the legendary C8, first introduced in 1970 and credited with transforming amateur astronomy. Today’s version retains its compact portability while delivering far superior performance. Measuring just 17 inches in length and weighing only 13 pounds, it’s easy to handle and transport - yet offers views that rival much larger instruments.

With an impressive 2032 mm focal length and f/10 focal ratio, this optical tube combines versatility with power. Thanks to Fastar compatibility, it can also be configured for ultra-fast imaging setups.

Equipped with Celestron’s patented StarBright® XLT coatings, the C8-A delivers brighter, sharper images across a wide range of celestial targets. These coatings significantly improve light transmission and contrast, allowing you to observe fine lunar and planetary details as well as faint galaxies and nebulae. For astrophotographers, the improved transmission translates to shorter exposure times and better image quality.

The C8-A comes with a CGEM-style dovetail bar, making it compatible with a wide variety of computerized equatorial and alt-azimuth mounts. This versatility ensures you can easily integrate the optical tube into your existing setup or pair it with a mount that matches your observing style.

Fastar Technology – Ultra-Fast Imaging

Celestron’s partnership with SBIG in 1997 brought about Fastar technology, a breakthrough for astrophotographers. With Fastar, the secondary mirror can be removed and replaced by a third-party lens assembly, allowing a CCD or CMOS camera to image directly at the f/2 primary mirror focus.

This system provides a dramatic advantage: exposures are up to 25× shorter compared to imaging at the native f/10 focal ratio. Deep-sky targets such as galaxies and nebulae can be captured in as little as 30 seconds, opening up fast and efficient astrophotography opportunities.

StarBright XLT Optical Coatings

The StarBright XLT system is among the most advanced coating technologies in the telescope industry. It consists of:

   ➜  Enhanced multi-layer mirror coatings made from aluminum, quartz (SiO₂), titanium dioxide (TiO₂), and additional SiO₂ layers for uniform reflectivity across the visual spectrum.

   ➜  Multi-layer anti-reflective coatings using magnesium fluoride (MgF₂) and hafnium dioxide (HfO₂). The rare element hafnium allows a broader bandpass than titanium-based coatings used in other systems.

   ➜  High-transmission water-white glass corrector plate, transmitting ~90.5% of light even before coatings. When combined with the XLT system, transmission reaches an average of 97.4%, ensuring maximum brightness and clarity.