The CPC Deluxe 925 HD Computerized Telescope from Celestron features an EdgeHD 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 an f/10 focal ratio. The EdgeHD optics delivers pinpoint, aberration-free images even with the widest field eyepiece. These optics are designed to produce an extremely flat focal plane precise enough to match the strict tolerances of large commercial CCD detectors, allowing all stars to be in tight focus to the very edge of the chip. Mirror tension locks hold the primary mirror in place and reduce image shift. There are cooling vents to allow hot air to be released from behind the primary mirror. There is FASTAR compatibility for fast f/2 CCD imaging.
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 a standard SCT telescope.
The StarBright XLT coatings are designed to produce fairly flat reflectivity across the spectrum, optimized for both CCD imaging and visual use. This high performance optical system utilizes multi-layer, anti-reflective coatings and high transmission Water White glass for the corrector lens.
The OTA comes with a very useful 9x50 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" diagonal inverts this image so it is right-side-up, but reversed. This diagonal directly accepts 2" eyepieces and comes with a 1.25" adapter. It is packaged with a 23mm, 82° Luminos eyepiece.
The dual fork arm mount is fully computerized with a database of over 40,000+ celestial objects, user definable filter limits and a "Solar System Align" that allows alignment on the Sun or Moon for daytime observing. The dual fork arm mount is a sturdy and reliable mount with a heavy-duty tripod featuring sturdy 2" stainless steel legs and an accessory tray. 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. A convenient remote hand controller allows you to view information hands-free. The NexStar program's advanced pointing feature further improves the pointing accuracy. Additionally, extended meridian tracking will track continuously through the Meridian.
The internal GPS receiver automatically downloads the date and time from orbiting satellites and pinpoints the telescopes exact terrestrial location. The need to manually enter the date, time, longitude and latitude with possible human-error is eliminated. SkyAlign extends the positioning to provide pinpoint accuracy with the hand controller.
The All-Star polar alignment procedure, with Celestron's optional Pro Wedge, allows the choice of any bright star and the software then calculates and assists with polar alignment for more precise accuracy. NexRemote allows control of the computerized telescope from a personal computer. Everything that is usually done with the telescope's hand control can be done remotely from a PC or laptop. Software can be kept current with downloadable flash upgrades via the Internet.
A re-engineered drive train with a larger 6", 180 tooth brass gear, a .75" stainless steel worm gear, together with a unique steel and nylon roller bearing, rotating around a wide 9.8 track furnishes very smooth tracking accuracy indeed. The Permanent Periodic Error Correction (PEC) allows users to train out the worm gears periodic errors, while the mount retains the PEC recordings - a welcome enhancement for astronomical imagers. Redesigned electronics delivers constantly regulated power to the telescope even when not perfectly balanced giving it the capability of smooth tracking motion and pin- point accuracy.