- Flat field free of optical aberrations like field curvature, coma, astigmatism and chromatic aberration across an entire APS-C sensor.
- Unlike the larger RASAs that work with DSLR and large CCD cameras, the 8” model was designed with color astronomical CMOS cameras, smaller CCD cameras, and mirrorless cameras in mind. The telescope does not work with standard DSLR cameras.
- Ultra-Stable Focus System – precision linear ball bearing virtually eliminates image shift.
- Internal filter mount – seamlessly accommodates a Light Pollution Imaging Filter into the optical path.
- Performs over a wider spectral range than most telescopes, from 400 - 800 nm, so more of the light passing through the astrograph is in sharp focus.
- The CGEM II, with its 40 lbs load capacity, is the latest update to the venerable CGEM mount and provides a sturdy and rigid platform for the fully-loaded RASA 8.
- The drive system, consisting of low cog DC Servo motors with integrated optical encoders, steel worm gears supported by precision sealed bearings, and brass worm wheels, ensures smooth and accurate slewing and tracking.
- Proven NexStar+ computerized telescope control technology supports functions to address imagers’ needs, such as All-Star Polar Alignment, Permanent Periodic Error Correction (PPEC), and adjustable tracking through meridian.
| Optical Tube Info: | |
| Optical Design: | Rowe-Ackermann Schmidt Astrograph |
| Aperture: | 203mm (8") |
| Focal Length: | 400mm (15.74") |
| Focal Ratio: | f/2.0 |
| Central obstruction diameter: | 93mm (3.66") (46% of aperture diameter) |
| Light Gathering Power (Compared to human eye): | 843x |
| Resolution (Rayleigh): | 0.68 arc seconds |
| Resolution (Dawes): | 0.57 arc seconds |
| Image Circle: | 22mm (.86") Ø, 3.15° |
| Useable field: | 32mm (1.26") Ø, 4.6°, only minimal performance loss at edge of FOV |
| Wavelength range: | 400 - 800 nm |
| Spot size: | < 4.6 μm RMS across image circle |
| Optical Coatings: | StarBright XLT |
| Off-axis Illumination: | 93% at 11mm (.43") off-axis |
| Optical Window: | 46mm (1.81") Ø |
| Back focus with included camera adapter: | 25mm (.98") |
| Back focus from top of threaded collar: | 29mm (1.14") |
| Optical Tube: | Aluminum |
| Optical Tube Length: | 628mm (24.7") |
| Optical Tube Diameter: | 235mm (9.3") |
| Focuser: | Ultra-Stable Focusing System |
| Finderscope: | Not included |
| Optical Tube Weight: | 17 lbs (7.7 kg) |
| Other Features: | Air-cooling system, integrated filter mount |
| Included items: | M42 camera adapter, C-thread camera adapter, fan battery pack |
| Dovetail: | CGE Dovetail Bar |
| Mount Info: | |
| Mount Type: | Computerized Equatorial |
| Instrument load capacity: | 40 lbs (18 kg) |
| Height adjustment range (includes mount and tripod): | 1346mm - 1651mm (53" – 65") |
| Tripod Leg Diameter: | 50.8mm (2") Steel tripod with graduated markings on lower section |
| Latitude adjustment range: | 15° - 70° |
| Mount Head Weight: | 40 lbs (18.14 kg) |
| Accessory Tray: | Yes |
| Tripod Weight: | 20 lbs (9 kg) |
| Weight of Counterweights: | 1 x 17 lbs |
| Slew Speeds: | 9 slew speeds - max speed 4.5°/second |
| Tracking Rates: | Sidereal, Solar and Lunar |
| Tracking Modes: | EQ North and EQ South |
| GPS: | N/A |
| Dovetail Compatibility: | Dual saddle plates (CG-5 and CGE saddle) |
| Number of Auxiliary Ports: | 2 AUX Ports (1x Hand control Port and 1x AUX Port for optional accessories) |
| Autoguide Port: | Yes |
| USB Port: | Yes, input on Hand Control |
| Power Requirements: | 12V DC, 3.2 amps |
| Motor Drive: | DC servo motors |
| Alignment Procedures: | 2-Star Align, 1-Star Align, Solar System Align, Last Alignment, Quick Align |
| Periodic Error Correction: | Yes |
| Computerized Hand Control: | 2 line x 18 character backlit Liquid Crystal Display, 19 LED backlit buttons, USB 2.0 Port for PC connection |
| NexStar+ Database: | 40,000+ objects, 100 user defined programmable objects Enhanced information on over 200 objects |
| Software: | Celestron Starry Night Special Edition Software and SkyPortal App |
| Total Kit Weight: | 95 lbs (43 kg) |
| Included Items: | CGEM II Equatorial Head Tripod Accessory Tray 1 x 17 lbs counterweight NexStar+ Hand Control DC Power Cable (item#18769) Hand Control Holster |