Orion 8" f/8 Ritchey-Chretien Astrograph Telescope
As any prolific astrophotographer will tell you, the more light you can gather, the better your astrophotos will turn out. Combine light-gathering prowess with a compact design and an affordable price, and you're likely to end up with our new 8" f/8 Ritchey-Chretien Astrograph. As a leading supplier of affordable imaging equipment and solutions for amateur astronomers, Orion is proud to introduce this highly regarded telescope design used by advanced astrophotographers and professional observatories worldwide — and even by the Hubble Space Telescope!
Previously available only in larger apertures that cost thousands more, the outstanding optical design of the Orion 8" Ritchey-Chretien Astrograph will allow you to capture spectacular, detailed images of deep-sky objects like never before. In contrast to conventional Newtonian reflector and Schmidt-Cassegrain designs that are susceptible to coma away from the center of the field, the Ritchey-Chretien utilizes hyperbolic primary and secondary mirrors to achieve wonderfully flat images that are virtually coma-free. In our 8" model, the mirrors are made of BK-7 optical glass with enhanced aluminum 94% - 96% reflectivity coatings, to provide diffraction-limited performance. Since there are no lenses involved, images are also free from chromatic aberration, which affects all but the finest, most expensive apochromatic refractors.
The Orion 8" Ritchey-Chretien Astrograph Telescope is ideal for use with small CCD-chip cameras such as our award-winning StarShoot line, as well as medium-format CCD and DSLR cameras, for deep-sky and solar system astrophotography. The telescope's wide, fully illuminated flat field produces pinpoint star clarity all the way to the edge of the camera's sensor.
The Orion 8" Ritchey-Chretien Astrograph features a machined, dual-speed (10:1) linear-bearing Crayford-style focuser with an engraved millimeter scale on the drawtube. The robust focuser provides precise fine focus adjustment without slippage or flexure with heavy accessories attached. One 2-inch and two 1-inch extension rings are included for adjusting the focus position for various cameras. Focus travel readily accommodates popular imaging accessories.
Orion Ritchey-Chretien Astrographs have been designed with collimation in mind. With an optical instrument of this caliber, precise optical alignment is of paramount importance. Each Orion RC secondary mirror is precisely center-marked to facilitate collimation and we even include a Cheshire collimation tool to make proper alignment of optics as convenient as possible.
The 21-inch enameled steel optical tube weighs only 15.8 lbs. and features a dovetail mounting bar underneath, for trouble-free setup on medium or large-sized Orion equatorial mounts. The inside of the optical tube is fortified with ten computer-positioned light baffles, and the primary mirror baffle tube and secondary mirror light shield are also highly baffled to ensure maximum image contrast.
Without a doubt, our 8" Ritchey-Chretien Astrograph brings advanced astrophotography performance into the realm of affordability for most amateur astronomers. More affordable than comparably sized apochromatic refractors and without the coma that afflicts Newtonian reflectors, the Orion 8" f/8 Ritchey-Chretien Astrograph Telescope will take your astrophotography to new heights!
|Custom Stock Status||In Stock|
|Focuser||2" dual-speed linear bearing Crayford|
|Highest Useful Magnification||300x|
|Included Accessories||Two 1" and one 2" removable extension tubes, Orion collimation tool|
|Limiting Stellar Magnitude||14.2|
|Lowest Useful Magnification||29x|
|Optical Tube Length||21.8 in.|
|Optical Tube Weight||15.8 lbs.|
|Secondary Mirror Obstruction||97mm|
|Secondary Mirror Obstruction by Area||23%|
|Secondary Mirror Obstruction by Diameter||48%|