Celestron CGEM II 925 SCT

9.25" Schmidt-Cassegrain Optics: 1127x Light Gathering Power

The 9.25" optical tube is a sweet spot in the Celestron lineup, offering a significant jump in light-gathering power over an 8" model without the weight and portability challenges of an 11". Its f/10 focal ratio and 2350mm focal length are ideal for resolving fine detail, capable of reaching a theoretical Dawes' limit of 0.49 arc seconds. Celestron's proprietary StarBright XLT optical coatings maximize light transmission, delivering brighter images and higher contrast on everything from the Cassini Division in Saturn's rings to faint galaxy clusters.

CGEM II Mount: A 40 lb Payload Capacity for Stable Imaging

Engineered as a serious astrophotography platform, the CGEM II mount provides the stability required for long-exposure imaging. It features a heavy-duty tripod with 2" diameter steel legs, a dual-fit CG-5/CGE saddle to accommodate various optical tubes, and a total instrument capacity of 40 lbs. Ergonomic details like large, easy-to-use adjustment knobs for altitude and azimuth simplify polar alignment, while internal motor wiring prevents cable snags during operation.

NexStar+ GoTo System: 40,000+ Objects at 4.5° Per Second

At the heart of the CGEM II 925 is the proven NexStar+ computerized system. The hand controller's database contains over 40,000 celestial objects, including planets, nebulae, galaxies, and star clusters, with enhanced information available for over 200 of the best targets. After a simple alignment procedure, the mount can automatically locate and track any object in its database with 9 available slew speeds, topping out at a rapid 4.5° per second.

Imaging-Focused Engineering: All-Star Alignment and PEC

The CGEM II includes features specifically for astrophotographers. Celestron’s All-Star polar alignment routine allows you to use any bright star to achieve an accurate polar alignment, even if Polaris is obstructed. For precision tracking, Permanent Periodic Error Correction (PEC) lets you train the mount to compensate for the minor mechanical imperfections in the worm gears, an essential step for eliminating trailed stars in long exposures. The mount is also designed to track well past the meridian, preventing interruptions when imaging an object through the best part of the night sky.

CGEM II 925 vs. Advanced VX 9.25": The Mount Makes the Difference

While both systems use the same excellent 9.25" optical tube, the CGEM II mount offers a significant upgrade over the Advanced VX for imagers. The primary advantage is payload capacity and stability for astrophotography.

• Payload Capacity: The CGEM II supports 40 lbs, a full 10 lbs more than the Advanced VX. This extra capacity is critical when adding a guide scope, a large camera, a filter wheel, and other accessories.
• Tripod and Stability: The CGEM II's 2" diameter steel tripod legs provide a much more rigid and vibration-resistant base than the 1.75" legs on the AVX, which translates to sharper images.
• Tracking Precision: Features like PEC and the ability to track past the meridian make the CGEM II a more capable and forgiving platform for serious, long-exposure astrophotography.