- 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 390-800 nm, so more of the light passing through the astrograph is in sharp focus.
- The CGX, with its 55 lb load capacity, is Celestron’s most innovative, state-of-the art, computerized equatorial mount to date, and provides a very sturdy and rigid platform for the fully-loaded RASA 8.
- The drive system utilizes low cog DC Servo motors with integrated optical encoders, belt and pulley motor connection, spring-loaded steel worm gears supported by precision sealed bearings, and brass worm wheels for smooth, accurate slewing and tracking performance with little backlash.
- Fully remote imaging capable, with optical limit switches, home sensors, through-mount cabling, and hard stops.
- Included Celestron PWI software allows direct computer control via USB 2.0 connection.
- 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.
This kit combines the 8” Rowe-Ackermann Schmidt Astrograph (RASA) with the state-of-the-art CGX German equatorial mount. Simply add a camera and this package offers everything you need to take spectacular images of wide-field deep sky objects. Although about the same size as the CGEM II, the CGX is a big step up in performance and features, especially for imaging applications.
RASA Performance Made for Everyone
Capture spectacular wide-field deep sky images in seconds with Celestron’s portable astrograph, the 8” Rowe-Ackermann Schmidt Astrograph (RASA). This incredibly fast f/2.0 system is the perfect companion to today’s color astronomical CMOS cameras, smaller CCD cameras, and mirrorless cameras. Thanks to its fast focal ratio and patented optical design, you can produce sharp, detailed images and, in many cases, skip the autoguider completely. Weighing in at just 17 pounds, it’s easy to transport your 8” RASA to the most remote dark sky locations.
The 8” RASA is an imaging telescope that delivers a flat-field without optical aberrations for razor sharp stars across a wide field-of-view. It can capture stunning deep-sky astronomical images without the challenges typically presented by longer focal length instruments at a fraction of the cost of those systems.
The latest addition to the RASA family, this 8” version is a much more portable and affordable version of the heralded RASA 11, which was introduced to much acclaim in 2014. With the 8” RASA joining the lineup, a wider range of astroimagers can enjoy the benefits of the RASA design. It has many of the same thoughtfully designed features as its “big brother” RASA 11, including the integrated air-cooling system, internal filter mount, and sturdy CGE dovetail mounting bar.
Purely designed for imaging, the 8” RASA cannot be used visually. The prime focus focal plane is located at the front of the optical system, so it cannot accommodate a traditional eyepiece.
Shorter Exposure Times and Virtual “Real-Time” Observing
Since it is an F/2.0 optical system, imagers can use shorter exposure times to capture detail in faint objects. When combined with sensitive cameras and the proper “live stacking” software, the 8” RASA can provide an almost real-time observing experience. View images on a computer instantly that are brighter and more detailed than can be seen in much bigger telescopes with the naked eye.
Ultra-Stable Focus System
With the launch of the 8” RASA, Celestron is unveiling a focuser design that mitigates lateral movement of the primary mirror when focusing, slewing, or tracking with the astrograph. Focusing is easier, more accurate, and more stable than ever. The key to the Ultra-Stable Focus System is a precision linear ball bearing, which is tested during assembly to ensure optimal results.
Built for Today’s Latest Cameras
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. It is optimized for sensors with up to a 22mm diagonal, but performs well with sensors up to 32mm diagonal. The APS-C sized sensors used in many mirrorless cameras are a good choice. 42mm full frame sensors will also work, but performance will be poor at the edges of the sensor and field illumination will be reduced. Additionally, we do not recommend pairing RASA 8 with any camera body more than 4” in diameter.
CGX Mount and Tripod Features
- Sturdier and more rigid with quicker dampening time
- Increased load capacity to 55 lbs.
- Motors provide more torque, better slewing and tracking under heavy loads
- Heavy Duty belt-drive system minimizes backlash while providing smooth motor operation under heavy loads
- Spring-loaded brass worm wheel and stainless steel worm gear reduce friction and provide optimum gear mesh
- Internal cabling for worry-free remote operation. Power input and accessory ports remain stationary while the mount slews to avoid snags
- Internal hard stops for both axes prevents cable tension and tripod strike
- Internal optical sensors on both axes for simple and safe remote operation
- Home sensors allow the mount to always start in the index position regardless of orientation before a power reset
- Limit sensors automatically shut off slewing or tracking before reaching the hard stop fail safe
- Control software developed in conjunction with PlaneWave Instruments for professional level control operation and imaging
- Software includes multi-point mount modeling for extremely precise pointing accuracy and many more additional features for remote astroimaging
- Wider tripod stance for improved stability
- Adjustable EQ head position to optimize center of gravity over the tripod and fully utilize the increased 3°-65° latitude range
- Dual-fit CG-5/Vixen and CGE/Losmandy dovetail saddle
- 2" steel legs with height index marks for quick leveling
- "Jack of all trays" can hold three 1.25" eyepieces, two 2" eyepieces, your smartphone, or other accessories
- +20° of additional tracking past the meridian on either side
- Tripod legs can be collapsed with accessory tray installed for faster setup and transport
- Two handles for easy pickup and transport
- Ergonomically designed dovetail clamping knobs
- Innovative and improved polar alignment adjustment system
- Ergonomic latitude adjuster for smooth and easy adjustment under full loads
- Optional add-on polar axis finderscope
- NexStar+ hand control with USB port
- Two AUX accessory ports to support wireless/WiFi alignment and operation with StarSense AutoAlign and SkyPortal WiFi Module accessories (sold separately)
- USB 2.0 port, used to connect directly to PC with included software
- Autoguider port
- PPEC ready
- Threaded 12VDC power input barrel connector
- Internal Real Time Clock (keeps time and site information saved
|OPTICAL TUBE INFO:|
|Optical Design||Rowe-Ackermann Schmidt Astrograph|
|Focal Length||400mm (15.74")|
|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||390 - 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 Length||628mm (24.7")|
|Optical Tube Diameter||235mm (9.3")|
|Focuser||Ultra-Stable Focusing System|
|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 Type||Computerized Equatorial|
|Instrument load capacity||55 lbs (25 kg)|
|Height adjustment range (includes mount and tripod)||1200.15mm - 1968.5mm (47.25" - 77.5")|
|Tripod Leg Diameter||50.8mm (2") Steel tripod with graduated markings on lower section|
|Latitude adjustment range||3° - 65°|
|Mount Head Weight||44 lbs (20 kg)|
|Tripod Weight||19.2 lbs (8.7 kg)|
|Weight of Counterweights||2 x 11 lbs|
|Slew Speeds||9 slew speeds - max speed 4°/second|
|Tracking Rates||Sidereal, Solar and Lunar|
|Tracking Modes||EQ North & EQ South|
|Dovetail Compatibility||Dual saddle plates (CG-5 and CGE saddle)|
|Number of Auxiliary ports||2 Aux ports (Hand Control can use either Aux port)|
|USB Port||Yes, input for Mount and Hand Control|
|Power Requirements||12V DC, 4 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||CPWI Telescope Control Software, Celestron Starry Night Special Edition Software, SkyPortal App|
|Total Kit Weight||124.2 lbs (56.3 kg)|
|Included Items||CGX Equatorial Head | CGX Tripod | Accessory Tray | 2 x 11 lbs counterweights | NexStar+ Hand Control | 8mm Allen Wrench | 12V DC Power Cable | Hand Control Holster|
Delivery Weight Package