Order By Phone
STORE FRONT: 5348 Topanga Canyon Blvd, Woodland Hills CA 91364


Orion - 10 " f/8 Ritchey Cretien Optical Tube Assembly


Be the first to review this product

Availability: Place your order to join our wait list - no deposit required.


Place your order to join our wait list - no deposit required.

Manufactured by: Orion

Orion 10" f/8 Ritchey Cretien Optical Tube Assembly


Orion 10" f/8 OTA

  • 10 inches of aperture gobble up delicate details of deep-sky objects
  • Ritchey-Chretien optical design produces wonderfully flat, virtually coma-free images superior to those achievable with conventional reflector or Schmidt-Cassergain telescope designs
  • Ideal for use with both medium and large-format CCD cameras and DSLRs; provides a wide, fully illuminated field and pinpoint star clarity out to the edge of the sensor
  • Features a 3-inch rotatable, machined, dual-speed (10:1) linear-bearing Crayford focuser that provides fine focus adjustment without slippage or flexure with heavy accessories attached
  • Designed with collimation in-mind, Orion RC's feature a precisely center-marked secondary mirror and include a Cheshire collimating tool, making them the most convenient RC's to collimate available
  • Optical tube has nine computer-positioned internal light baffles to ensure maximum contrast; primary mirror tube is internally micro-baffled.



Go after even the most elusive and faint deep-sky targets with the Orion 10" f/8.0 Ritchey-Chretien Astrograph. Featuring virtually coma-free optics for superb imaging performance, the Orion 10" f/8.0 Ritchey-Chretien Astrograph boasts a plethora of deluxe features. Its precision hyperbolic primary and secondary mirrors are made of highest quality quartz optical glass with enhanced reflectivity (94-96%) aluminum coatings. The machined aluminum, dual-speed (10:1) 3" modified Crayford focuser with linear track bearing provides rigid, backlash-free support for hefty imaging accessories. Nine knife-edge computer-positioned internal light baffles in the optical tube, primary mirror tube baffles, and a baffled secondary mirror shield ensure maximum image contrast and brightness. Three 1.5" DC cooling fans built into the rear cell help to reduce cooldown time for the telescope to reach thermal equilibrium. Two wide "Losmandy-style" dovetail mounting plates are attached to both the top and bottom of the tube for easy mount attachment and use of optional guide scope for guided CCD imaging pursuits.






Additional Information

Name Orion - 10 " f/8 Ritchey Cretien Optical Tube Assembly
Manufacturer Orion
Model 08961
Manufacturer Part No 08961
Custom Stock Status Place your order to join our wait list - no deposit required.
Diameter 250mm
Focal Length 2000mm
Focal Ratio f/8.0
Focuser 3in. dual-speed linear bearing Crayford
Highest Useful Magnification 300x
Included Accessories Two 1in. and one 2in. removable extension tubes, Orion collimation tool, Quartz primary and secondary mirrors
Limiting Stellar Magnitude 14.7
Lowest Useful Magnification 36x
Mount Optical Tube without Mount
Optical Design Ritchey-Chretien
Optical Tube Steel
Optical Tube Length 29.0 in
Secondary Mirror Obstruction 111mm
Secondary Mirror Obstruction by Diameter 44%
Warranty One year