Celestron RASA 11" Rowe-Ackermann Schmidt Astrograph V2 OTA

Capturing stunning deep-sky images is easier with Celestron’s Rowe-Ackermann Schmidt Astrograph (RASA) V2. Designed for modern DSLR and astronomical CCD cameras, its fast, wide-field f/2.2 optical system allows for shorter exposure times than traditional f/10 astroimaging while maintaining excellent resolution. The shorter exposures and 620mm focal length also reduce the tracking demands on your equatorial mount, and in many cases, autoguiding may not be necessary. Building on Celestron’s legacy of Schmidt Cameras, the RASA 11 V2 is designed for modern large-format imaging sensors. Its 43.3mm optimized image circle delivers sharp, pinpoint stars across large imaging chips, with excellent optical performance for sensors with diagonals up to 52mm. With its wide image circle and short 620mm focal length, the RASA 11 V2 is ideal for wide-field astrophotography, large night-sky mosaics, astronomical surveys, and even comet hunting.

Optical Performance

The RASA 11 V2 features optics with 4-element rare-earth glass for images free of false color and aberrations like coma and field curvature. The optical quality and spot size across the entire image circle are unprecedented for an astrograph in this price range—or even that of a much more expensive instrument. The design also provides minimal vignetting.

Advanced Features

RASA 11 V2 utilizes the new Ultra-Stable Focus System (USFS). At the heart of this system is a precision linear ball bearing. The bearing serves to minimize focus shift (unwanted lateral motion of the primary mirror during focusing which causes shifting of the image) and mirror flop (movement of the primary mirror when the telescope is pointing to different positions in the sky). The USFS is also compatible with the optional Celestron Focus Motor (#94155-A). The integrated 12V DC MagLev fan reduces cooldown time and provides optimal airflow through the dust filtered optical tube. Engineered as a complete astroimaging system, every component of the RASA 11 V2 is optimized for peak performance with DSLR and astronomical CCD cameras. Down to the thickness of the glass used in the included fully-multicoated optical window or optional imaging filter, every component of the system has been taken into careful consideration to work together seamlessly. The Dovetail CGE bars on the top of the optical tube provides a connection for use of optional accessories like a guidescope.

Features

• Fast, wide-field 11” f/2.2 optical design with rare-earth glass for images free of false color, coma, and field curvature
• Large 43.3mm optimized image circle maintains pinpoint stars to the far corners of even the largest astroimaging sensors, while the usable field extends even further to 52mm for larger format sensors
• New Ultra-Stable Focus System (USFS) minimizes focus shift and mirror flop
• Integrated air-cooling system features a quiet, high-output 12V MagLev fan and vents with mesh filters to prevent dust ingress
• Common camera adapters (T-thread and M48) included for easy attachment to popular CCD and DSLR cameras