Celestron EDGEHD 9.25" Optical Tube Assembly (CGE Dovetail)

See the Universe in HD

EdgeHD is an aplanatic Schmidt telescope designed to produce aberration-free images across a wide visual and photographic field of view. The optical system was designed to reduce more than just off-axis star coma, but also to give an astrograph quality flat focal plane all the way to the edge of the field of view.

True Astrograph Quality

Many optical designs that advertise themselves as "astrograph" quality actually only produce pinpoint stars across a curved focal plane. While this may be acceptable for visual observing, stars will appear out of focus at the edge when used with a flat chip sensor of a digital camera. EdgeHD optics produce a focal plane more than three-times flatter than a standard Schmidt Cassegrain telescope and dramatically flatter than other competing coma-free designs. This guarantees you visibly sharp stars across some of the largest CCD chips available today.

Improved Performance

Superior edge performance not only creates rounder, more pleasing stars but actually improves the resolution and limiting magnitude when compared to telescopes of equal aperture. Starbright XLT® Coatings coupled with Celestron's StarBright XLT coating group on every surface, EdgeHD optics gives you maximum light throughput across the widest visual and photographic spectrum.

Mechanical Features

In addition to Celestron's new optimized optical design, the EdgeHD tube has been redesigned to make sure you get the most from your optics each and every night.

• Mirror Clutches - Flexible tension clutches hold the mirror in place and reduce image shift when rotating the tube around the mount. The flexible rods allow the mirror to be held in place without putting any force or pressure on the mirror assembly, keeping the image centered in the eyepiece (or chip).
• Tube Vents - Cooling vents located on the rear cell allow hot air to be released from behind the primary mirror. Each vent has an integrated 60 micron micro-mesh filter guaranteed to let warm air out without letting dust in.
• Fastar Versatility - EdgeHD is the most versatile imaging telescope available today. At its native f/10, you can achieve the image scale necessary to capture the smallest of deep sky objects. Add the optional 0.7x reducer lens — custom-designed for your size EdgeHD tube — and you can increase your field of view without sacrificing optical performance. A Barlow gives you added power for high-resolution planetary, lunar and solar imaging. All EdgeHD optical tubes are Fastar-compatible, allowing the secondary mirror to be removed and replaced with a third party lens accessory for ultra-fast f/2 wide field imaging.

Individually Tested

Every EdgeHD that ships has been tested not only for the surface quality of each optical component, but also with a camera and artificial star to ensure the imaging system meets our rigid quality assurance. This “final acceptance test” confirms the EdgeHD will perform in the field and deliver high-quality astroimages.

Specifications:

• Optical Design: EdgeHD (Flat Field Schmidt-Cassegrain Telescope)
• Aperture: 234.95mm (9.25")
• Focal Length: 2350mm (93")
• Focal Ratio: f/10
• Focal Length of Eyepiece 1: 23mm (0.91")
• Magnification of Eyepiece 1: 102x
• Finderscope: 9x50
• Star Diagonal: 2" with 1.25" adapter
• Optical Tube: Aluminum
• Highest Useful Magnification: 555x
• Lowest Useful Magnification: 34x
• Limiting Stellar Magnitude: 14.4
• Resolution (Rayleigh): 0.59 arc seconds
• Resolution (Dawes): 0.49 arc seconds
• Light Gathering Power (Compared to human eye): 1127x
• Image Circle: 42mm
• Secondary Mirror Obstruction: 85mm (3.35")
• Secondary Mirror Obstruction by Diameter: 36%
• Secondary Mirror Obstruction by Area: 13%
• Optical Coatings: StarBright XLT
• Optical Tube Length: 559mm (22")
• Optical Tube Diameter: 271.78mm (10.7")
• Optical Tube Weight: 21 lbs (9.53 kg)
• Dovetail: CGE Dovetail Bar

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.