Celestron C6 Optical Tube Assembly (CG-5 Dovetail)

Celestron C6 Optical Tube Assembly (CG-5 Dovetail)

The Celestron C6-A OTA is a highly versatile optical tube, delivering a 1500 mm focal length and an f/10 focal ratio. With 40% more light-gathering power than a 5-inch Cassegrain telescope, it offers brighter and sharper images. Equipped with Celestron’s exclusive StarBright® XLT optical coatings, the C6-A provides noticeably improved contrast and transmission, enabling shorter exposure times and better deep-sky performance. With this system, you can detect fine details on the Moon and planets while also exploring distant galaxies and nebulae.

This OTA comes with a CG-5 dovetail bar, making it compatible with a wide range of computerized telescope mounts. It also pairs well with a simple manual altazimuth mount, offering flexibility for casual stargazing at night or as a terrestrial spotting scope during the day.

The Celestron C6-A delivers an excellent balance of light-gathering ability, portability, ease of use, and value, making it one of the most accessible choices for amateur astronomers. It is designed as an advanced-level instrument yet remains as user-friendly as most entry- and intermediate-level telescopes.

StarBright XLT Coatings

Celestron’s StarBright XLT optical coating system is among the most advanced available, surpassing standard commercial coatings in performance. This system is built on three main components:

   ➜  Enhanced multi-layer mirror coatings composed of carefully layered aluminum, quartz (SiO₂), titanium dioxide (TiO₂), and additional quartz, delivering flat reflectivity across the visible spectrum for both imaging and visual observing.

   ➜  Multi-layer anti-reflective coatings made with magnesium fluoride (MgF₂) and hafnium dioxide (HfO₂). Hafnium, a rare and costly element, provides a broader bandpass than titanium, giving Celestron’s coatings an edge over competitors.

   ➜  High-transmission water-white glass corrector plate, which achieves ~90.5% light transmission before coatings–about 3.5% better than soda-lime glass. When paired with StarBright XLT’s anti-reflective coatings, transmission reaches an extraordinary 97.4%, ensuring maximum image brightness.