Celestron RASA 8" f/2 OTA
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Celestron RASA 8" f/2 OTA
The Rowe-Ackermann Schmidt Astrograph, known mainly as the Celestron RASA, became one of the best astrophotography telescopes the moment it was released. Since then, its popularity has only grown due to the incredibly fast optics for efficient imaging, absurdly clear optics from edge-to-edge of the aperture, and the fact that it's one of the most reasonably priced, professional-grade telescopes available. Any astrophotographer will say the same great things about the Celestron RASA astrograph telescope. Experience as close to perfection as you can get in a portable package with the RASA series telescopes.
Fast Optics for Short Exposures and "Real-Time" Observing
Use shorter exposure times to capture details in faint objects with its f/2.2 optical system. When combined with sensitive cameras and the proper live-stacking software, the 8-inch RASA can provide an almost real-time observing experience. Instantly view images on a computer that are brighter and more detailed than what you would see with the naked eye threw bigger telescopes.
Because shorter exposure times are possible, your equatorial mount won’t need to accurately track over extended periods. The 8-inch RASA’s relatively short 400 mm focal length also lessens equatorial tracking demands. In many cases, autoguiding will not be required.
An Astrograph for Everyone
The 8-inch 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.
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.
Focusing Made Easy
Focusing is easier, more accurate, and more stable with its new focuser design that mitigates lateral movement of the primary mirror when tracking, focusing, or slewing. Two sets of precision bearings are precisely aligned and tested during assembly to ensure optimal results.
Imaging in the Modern Age
Designed to pair with color astronomical CMOS cameras, smaller CCD cameras, and mirrorless cameras, it is optimized for sensors with up to a 22 mm diagonal. It can accept larger sensors (up to a 32 mm diagonal) as well as APS-C sized sensors used in many mirrorless cameras.
Below you'll see an incredible image of the Rosette Nebula taken by Jason Guenzel using the Triad Ultra filter on the super-fast f/2.2 Celestron RASA telescope!
Camera adapters, to connect C-mount cameras and cameras which mount with M42 threads are included.
Please note: The 8-inch RASA will not work with standard DSLR + T-Ring systems. OPT offers optional adapters to connect your 8-inch RASA to a Sony(#CE-93405), Canon(#CE-93406), or other mirrorless cameras.
Highlighted Features of the Celestron RASA
- Designed with a Schmidt corrector, primary mirror, lens group, and optical window.
- The 8-inch RASA’s optics are designed to perform over a wider spectral range, from 390 to 800 nm. This allows more of the light emitted from the astronomical object to be sharply focused in the image.
- A removable optical window, so you can maintain peak optical performance if a filter is added or if a camera has its own optical window.
- OPT offers a Celestron light pollution imaging filter designed specifically for the 8-inch RASA, which mounts in place of the optical window.
- All refractive optical surfaces are coated with StarBright XLT coatings, while the primary mirror uses enhanced aluminum coatings.
|Aperture||203 mm (8")|
|Corrected Image Circle||22mm|
|Dawes Limit||0.57 arcseconds|
|Focal Length||400 mm|
|Light Gathering Power||841x|
|RMS Spot Size||4.6 microns|
|Tube Weight||17 lbs|
- 8-inch RASA Telescope.
- M42 camera adapter.
- C-thread camera adapter.
- Fan battery pack.
Optics are excellent, but the plastic ring that holds the corrector plate is so cheap looking and warped that I almost sent it back. Overall is a great scope to have.
Easy to handle. Great wide field views of Veil, North America Nebula, etc. with short exposures and low gain. Additional extenders needed to get the spacing right for the camera and tricky to figure out.
I am using a MallinCam DS16c with my RASA 8" and it is phenomenal. Exposure times are down and I can see previously unseeable objects from my backyard. Very, very pleased with this scope.
I am very happy with the 8" RASA! I added the Celestron filter for the RASA, the slide filter assembly and used a ZWO ASI183 camera. Placed on the Orion HDX110 with a 60mm guide scope and ZWO ASI290. I also tried it with the Sony a6300 camera which I found to have design issues with the adapter now that the Sony cameras have added the grip which rubs the retaining ring. Workable but annoying! John Glenn Astronomy Park, after the moon set. 8-9-19 and 8-10-19 I used the RASA on two nights. I can say, I was impressed with the 8" RASA and ZWO ASI183 combination! M31 was edge to edge in 120 seconds. M27 resolved picture perfect in 60 seconds. M57 was small yet amazing at 90 seconds. I also took several images of M33 ... 60 seconds it was a wispy fuzz, at 90 seconds it was pretty good, and at 120 seconds it was a picture worth sharing! I can't wait to stack a 20 frames of M33! ... ZWOair works well with the Orion HDX but don't forget the upload the latest firmware for both and add Skysafari 6 plus.
The 8” RASA hit the market at the right time. It is more affordable than the bigger siblings and also, because of its lighter weight, more versatile. The images come out crispier due to the new focusing system implemented in the new RASA. No more mirror locking needed. It’s a joy to use.
very happy with the RASA 8. Initially had trouble with mirror flop. The RASA 11 had mirror locking screws which have been removed in the RASA 8. I have suggested to Celestron that the Instruction Manual should make reference to mirror flop and what to do about it.