Celestron CGE PRO 925 HD Computerized Telescope

Description

CELESTRON CGE PRO 925 HD COMPUTERIZED TELESCOPE

The Celestron CGE PRO 925 HD Computerized Telescope from Celestron features a Schmidt-Cassegrain optical system. This compound, or catadioptric, light-path employs a combination of mirrors and lenses that offer a large high-resolution aperture, a shorter tube length, and enhanced portability. This telescope has a 9.25″ aperture, a focal length of 2350mm, and a focal ratio of f/10.

EdgeHD optics are designed to produce aberration-free images across a wide visual and photographic field of view. With a significant reduction in off-axis star coma and a flat astrograph quality image plane to the edges of the field of view, the EdgeHD system is capable of imaging diffraction limited stars of 1 arcsec at the edges of a full-frame sensor.

The optical path consists of a zero power corrector plate, a spherical primary mirror, and a secondary mirror along with a set of field flattening lenses integrated into the baffle tube. The resulting imaging plane is 3 times flatter than the field produced by standard SCT telescopes. EdgeHD telescopes feature StarBright XLT multi-layer coatings on the primary and secondary mirrors for increased reflectivity. The corrector is also fully coated to ensure enhanced anti-reflection characteristics.

EdgeHD optics optimize an image circle with a 42mm diameter around the center of the field of view. This circle completely covers the diagonal of a full-frame DSLR camera or a standard 35mm film frame. As such, it extends significantly beyond the diagonal of APS-C sensors and the smaller chips used in specialized astrophotography CCD cameras. Further refinement of the system’s imaging capabilities is managed via mirror tension clutches that help support the primary mirror and minimize its lateral movement. This enhancement is particularly important to astrophotographers as it significantly improves the system’s stability and imaging clarity.

The OTA comes with a very useful 9×50 finderscope fitted to its exterior. Due to its wider field of view, this ancillary optic can offer assistance in locating objects to view with the main scope.

Normal image orientation for the EdgeHD design is upside-down and reversed. The 2.0″ diagonal inverts this image so it is right-side-up, but reversed. This diagonal directly accepts 2.0″ eyepieces, and a 1.25″ eyepiece adapter is included. This kit comes packaged with Celestron’s Axiom LX 23mm eyepiece. This ocular is ideal for deep-space viewing – its wide field of view produces a feeling of being surrounded by the viewing experience.

The CGE PRO Mount is fully computerized with a database of over 40,000 celestial objects, and it offers numerous design advantages. With a payload capacity of 90 lb, the CGE PRO is capable of securing a fully-loaded telescope. The software-assisted all-star polar alignment feature allows the viewer to choose any bright star for alignment of the mount’s polar axis, even if the North Star isn’t visible. Large hand-knobs offer easy altitude and azimuth adjustments. With just a standard hand-control alignment, the CGE PRO is capable of centering a star to within 5 arc minutes. The NexStar program’s advanced pointing feature further improves the pointing accuracy to as low as 1 arc minute. Additionally, extended meridian tracking, fast slew speeds, and a precision tracking system all combine to provide outstanding tracking and viewing performance

Optical Performance

Aperture: 9.25″

EFL: 2350 mm, f/10

Schmidt-Cassegrain system for aberration-free imaging

Premium StarBright XLT coatings for enhanced light transmission

EdgeHD optics deliver crisp aberration-free images. They are designed to produce an extremely flat focal plane to match the strict tolerances of the largest commercial CCD detectors. They are capable of imaging a diffraction limited star of 1 arcsec at the very edge of a full frame camera chip.

Construction Details

Aluminum tube

Mirror support knobs reduce image shift

Filtered tube vents release hot air from behind the primary mirror

Dovetail rail: included in package – compatible with Celestron’s CGE mount

Fastar compatible: equipped with a removable secondary mirror for CCD imaging

9×50 finderscope

Angle of view: 5.8°

Assists in locating objects

All mounting hardware is included in kit

Axiom LX 23mm Wide Angle Eyepiece

AFOV: 82°

Eye Relief: 17 mm

Magnification: 102x with 9.25″ EdgeHD

Accepts Celestron’s 2.0″ thread-in filters

Parfocal design allows for fast switching of eyepieces

Delivers pinpoint images when used with a flat field telescope

Retractable eyecup provides ultra-low profile for eyeglass wearers

90° Diagonal

Accepts 2.0″ eyepieces

1.25″ eyepiece adapter included

Image orientation: right-side-up, laterally reversed

StarBright XLT multi-layer coatings enhance light transmission

Improved brass clamping ring provides a secure no-mar connection

CGE PRO Computerized Equatorial Mount

Maximum payload: 90 lb / 40.8 kg

Stainless steel tripod: 2.75″ legs, accessory tray, adjusts from 38 – 55″

Powered by the supplied car battery adapter or optional AC adapter (Celestron #18779)

NexStar technology: 40,000 object database, expanded information on 200+ objects, 100+ user-definable objects. Custom database lists famous deep-sky objects by name and catalog number

Double line, LED backlit 16-character LCD hand control simplifies ‘Go-To’ operation. NexRemote software for computerized telescope control via RS-232 port. Autoguide port, PC port, auxiliary ports located on the electronic pier for long exposure astrophotography. Flash upgradeable hand control, software, and motor control units. Product updates available over the

Internet

Programmable periodic error correction (PEC) corrects tracking errors

12VDC servo motors: integrated optical encoders and seven slot skewed armatures minimize magnetic cogging and noise to ensure quiet operation and long life. Precision made cut-steel gears improve tracking precision

Main shafts: crafted from 1.57″ steel tubing with 0.40″ wall thickness with two preloaded 2.68″ tapered roller bearings on both axes

Precision worm drive: 0 .75″ pitch diameter precision made steel worm gear is preloaded with two 0.87″ OD ball bearings to minimize run-out and periodic error

Precision worm wheel: 255 tooth 6.0″ pitch diameter with enveloping brass teeth

Spring loaded DEC worm minimizes backlash for easy guiding

4 point RA and DEC clutch system for no-slip pointing precision

Latitude range: 10- 65° for northern/southern hemispheres

Slew speeds: speeds 5.5, 2.0, 0.5 °/sec, 64x, 16x, 8x, 4x, 1x, 0.5x. Tracking rates: sidereal, solar, lunar. Tracking modes: EQ north/south. Alignment procedures: 2-star/1-star, solar system, last, quick. One 22.0 lb counterweight included

SPECIFICATIONS

• Optical Design: Schmidt-Cassegrain
• Aperture: 9.25″ / 235 mm
• Focal Length: 2350 mm / 92.52″
• Focal Ratio: f/10.0
• Resolving Power Rayleigh: 0.59 arc/sec
• Resolving Power Dawes: 0.49 arc/sec
• Minimum Magnification: 34x
• Maximum Magnification: 555x
• Dovetail Plate: Included, compatible with CGE mount
• Visual Back: Included
• Eyepiece Barrel Diameter: 2.0″ diagonal w/1.25″ adapter
• Finderscope: 9×50
• Optical Tube Dimensions Length: 22.0″ / 55.8 cm
• Weight OTA: 21.0 lb / 9.53 kg
• Tripod and Pier: 52 lb / 23.59 kg
• EQ Mount: 75 lb / 34.02 kg