Celestron CGX Equatorial 800 SCT

8" Schmidt-Cassegrain Optics with StarBright XLT Coatings

The heart of this system is the 8" Schmidt-Cassegrain optical tube assembly (OTA), which folds a 2032mm focal length into a 17-inch (432mm) tube.

To maximize the light reaching your eye or camera sensor, Celestron applies its patented StarBright XLT coatings: enhanced multi-layer mirror coatings, multi-layer anti-reflective coatings and a corrector of high-transmission water white glass, which visibly increase contrast and light transmission.

0.57" Resolution and 843x Light Gathering Power

The 8" (203.2mm) aperture is the engine of this telescope, defining its ability to resolve fine detail and capture faint light. The Dawes limit is 0.57 arc seconds, the Rayleigh limit 0.69 arc seconds, the light-gathering power 843 times the human eye and the limiting stellar magnitude 14.

The secondary mirror obstruction is 64mm (2.5"), 31% by diameter.

Fastar Compatibility: f/2 Imaging

A key feature of this optical tube is its compatibility with the Fastar system. The secondary mirror can be removed and replaced with a lens assembly sold separately by third-party manufacturers, so a camera can work at the front of the telescope at the f/2 focus of the primary mirror. Exposures are 25 times shorter than at f/10, and galaxies and nebulae can be captured in 30 seconds.

Never remove the secondary mirror except to install the optional lens assembly.

The CGX Mount Head: 55 lb Capacity

Celestron designed the CGX, successor to its CGEM line, to better support your telescope for both visual and astro-imaging pursuits. Its design goals were a lower profile EQ head, which provides a more compact and therefore more stable setup, a better drive system, home and limit optical sensors for remote operation, easier polar alignment adjustments and better cable management. The instrument load capacity is 55 lbs (25 kg).

Polar alignment uses altitude and azimuth adjustment knobs with altitude lock knobs, and latitude runs from 3° to 65°. The head has carry handles, and the 8mm Allen wrench required for attaching the head to the tripod is stored conveniently in the rear handle.

Drive, Sensors and Internal Cabling

DC servo motors drive both axes at 9 slew speeds up to 4° per second, with Sidereal, Solar and Lunar rates and an anti-backlash setting in the hand control. Internal switches take the mount to its home position at power-on, software limit sensors stop it near the end of its range, and a mechanical hard stop on each axis helps prevent the telescope striking the mount or tripod. The R.A. limit lets you track 20° past the meridian.

The CGX uses internal cabling and has 2 AUX ports, a dedicated autoguide port and a USB port.

The 2" Steel Tripod and Dual Saddle

The 19.2 lb tripod has 2" (50.8mm) steel legs with graduated markings on the lower section, and an accessory tray fits over its central column.

The dual saddle accepts both CG-5 (Vixen style) and CGE (Losmandy D style) dovetail bars; the 8" SCT comes on a CGE dovetail bar.

NexStar+ Controller: 40,000+ Objects and All-Star Polar Alignment

The NexStar+ hand control holds over 40,000 objects and offers 2-Star, 1-Star, Solar System, Last and Quick Align.

Celestron's All-Star Polar Alignment polar aligns the mount on a convenient bright star without Polaris or a polar axis finder, after a Two Star, One Star or Solar System Align.

PC Control: CPWI and ASCOM

The kit includes Celestron's CPWI Telescope Control Software, which connects to the USB port on the mount, plus Starry Night Special Edition and the SkyPortal app (with the optional SkyPortal WiFi module). For ASCOM or third-party software, connect your PC to the NexStar+ hand control's mini USB port.

Visual Observing: An 81x View Straight Out of the Box

The 25mm eyepiece gives 81x, with a 1.25" star diagonal and a 6x30 finderscope.

The focus knob moves the primary mirror along the baffle tube and takes about 30 turns from close focus to infinity. The highest useful magnification is 480x.

Solar Warning

Never look directly at the Sun with the naked eye or with an optic (unless you have the proper solar filter). Permanent and irreversible eye damage may result. Never use your optic to project an image of the Sun onto any surface. Internal heat build-up can damage the optic and any accessories attached to it. Never leave your optic unsupervised. Make sure an adult who is familiar with the correct operating procedures is with your optic at all times, especially when children are present.