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This is an 8" RASA OTA that's practically in "like-new" condition. The optics are clean; the body is unmarked. The previous owner said that they never got a chance to use it.
This is not the "kit" version of the OTA, so it does not include any filters. This is just the bare OTA alone, with a Losmandy dovetail.
We do have the packing box for this, so we can ship this to you.
- Ultra-fast Rowe-Ackermann Schmidt f/2.0 Optics – Don't spend hours capturing your images—with RASA 8's f/2.0 optical system, you can gather the same image brightness 25 times faster than an f/10 system. And RASA 8 images aren't just bright and full of detail; they're also free from optical defects like field curvature, coma, astigmatism, and chromatic aberration.
- Patented Technology that Researchers Trust – Beyond imaging, RASA is the perfect tool for detecting errant space junk and asteroids. Scientists and government agencies use RASA arrays to monitor the space environment and protect our satellites.
- Built for Today's Cameras – Designed with color astronomical CMOS cameras, smaller CCD cameras, and mirrorless cameras in mind, RASA 8's flat field provides pinpoint stars and excellent performance across an entire APS-C sensor.
- Ultra-Stable Focus System – A precision linear ball bearing virtually eliminates image shift. RASA performs over a wider spectral range than most telescopes, from 400 nm to 800 nm, so more of the light passing through the astrograph is in sharp focus.
Capture spectacular wide-field deep sky images in seconds with Celestron’s new 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.
RASA Performance Made for Everyone
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.
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.
Because shorter exposure times are possible, your equatorial mount won’t need to accurately track over extended periods. The 8” RASA’s relatively short 400mm focal length also lessens equatorial tracking demands. In many cases, autoguiding will not be required. Weighing only 17 lb, this optical tube pairs perfectly with a wide variety of mounts.
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. It is optimized for sensors with up to a 22mm diagonal, but still performs well with larger (up to 32mm diagonal) sensors. As such, it works well with APS-C sized sensors used in many mirrorless cameras.
Camera adapters to connect C-mount cameras and cameras which mount with M42 threads are included. Celestron offers optional adapters to connect your 8” RASA to Sony or Canon mirrorless cameras.
| OPTICAL TUBE INFO: | |
|---|---|
| Optical Design | Rowe-Ackermann Schmidt Astrograph |
| Aperture | 203 mm (8") |
| Focal Length | 400 mm (15.74") |
| Focal Ratio | f/2.0 |
| Central obstruction diameter | 93 mm (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 | 22 mm (.86") Ø, 3.15° |
| Useable field | 32 mm (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 11 mm (.43") off-axis |
| Optical Window | 46 mm (1.81") Ø |
| Back focus with included camera adapter | 25 mm (.98") |
| Back focus from top of threaded collar | 29 mm (1.14") |
| Optical Tube | Aluminum |
| Optical Tube Length | 628 mm (24.7") length, 235 mm (9.3") diameter |
| Focuser | Ultra-Stable Focusing System |
| Finderscope | Not included |
| Optical Tube Weight | 17 lbs (7.7 kg) |
| Other Features | Air-cooling system, integrated filter mount |
| Dovetail | CGE Dovetail Bar |