Focus Scientific

Celestron 279mm (11\") Rowe-Ackermann Schmidt-Astrograph (RASA) Imaging Telescope (OTA)

Produce impressive astro images with greater ease with the Celestron 11" Rowe-Ackermann Schmidt Astrograph. The fast f/2.2 system reduces exposure times, while providing lower sensitivity to tracking anomalies, to deliver sharp images. Utilizing newly designed rare earth glass containing four different rare earth materials, chromatic aberration and aberrations like coma and field curvature are eliminated.

The Rowe-Ackermann design delivers an image free of coma and field curvature, perfect for use with today's top DSLR and astro-imaging cameras with full-frame (or larger) sensors. The generous 70mm optimized image circle is suitable for even the largest of imaging sensors, with minimal vignetting and pin-point stars right to the corners.

Focusing has been improved by producing a custom engineered linear brass focuser bearing, and utilizing Starlight Instruments famous FeatherTouch Micro Focuser with 10:1 fine-focus.

The built-in MagLev cooling fan is a new generation of cooling fan. This isn't just another off-the-shelf PC cooling fan, but one of the highest quality fans available which is engineered to reduce vibration-inducing wobble, a chief contributor to fan bearing damage. By floating the rotating fan over a magnetic field, wobble is eliminated, vastly improving the longevity of the bearings, and eliminating the associated vibration. The cooling system is designed with built-in filters to prevent dust intrusion. The fan is designed to reduce the cool-down time, so imaging can begin sooner.

Every component of the Celestron Rowe-Ackermann Schmidt Astrograph imaging system has been optimized for peak performance. Whether you use a DSLR or astronomical CCD camera, or add an optional imaging filter, every component of the system has been taken into careful consideration to work together seamlessly.

This is not a visual telescope, but a sophisticated camera lens. It requires a DSLR camera or astro-imaging camera (sold separately) mounted in front of the telescope in order to produce an image.

Features

  • 11" f/2.2 optical design with rare-earth glass for images free of false color, coma, and field curvature
  • 70 mm optimized image circle maintains pinpoint stars to the far corners of even the largest astroimaging sensors
  • Custom engineered linear brass focuser bearing reduces image shift
  • Dual-speed 10:1 FeatherTouch Micro Focus Knob provides the most precise focusing
  • Quiet, high-output 12v MagLev fan reduces cooldown time and blocks dust
  • Common camera adapters (T-thread and M48) included for easy attachment to popular CCD and DSLR cameras

Specifications

  • Aperture: 279mm (11")
  • Focal length: 620mm (24")
  • Focal ratio: f/2.2
  • Optical design: Rowe-Ackermann Schmidt
  • Optical coatings: StarBright XLT
  • Focuser: Starlight Instruments Feathertouch w/ 10:1 fine focus
  • Cooling: 12v MagLev fan
  • Mirror lock: Yes
  • Image circle: 70mm (2.8")
  • Backfocus from front lens assembly: 69.26mm (2.7")
  • Backfocus from included camera adapters: 55mm (2.17")
  • Central obstruction diameter: 114mm (4.5")
  • Resolution (Rayleigh): 0.5 arc seconds
  • Resolution (Dawes): 0.41 arc seconds
  • Finderscope: Not included
  • Eyepieces: Not applicable
  • Star diagonal: Not applicable
  • Length: to be determined
  • Weight: 15.9kg (35lbs)
  • Color: White and black
  • Celestron two year limited warranty