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Bintel Glebe
Usually ready for pickup in 24 hours
Bintel 84 Wentworth park road, Glebe, 2073, NSW
Phone:(02) 9518 7255
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Celestron 8" F/2 RASA - 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.
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.
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.
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.
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 two sets of precision bearings that are precisely aligned and 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. See the chart below to determine if your camera is compatible with RASA 8.
| Camera | Compatible with RASA 8? | Adapter required |
|---|---|---|
| Astronomical CMOS/CCD camera with C-mount | Yes | C-mount adapter (included) |
| Astronomical CMOS/CCD camera with M42-thread mount | Yes | M42 adapter (included) with M42 extension tubes (not included) |
| Astronomical CMOS/CCD camera with other mount | Yes | Custom camera adapter |
| Canon mirrorless with APS-C sensor | Yes |
Canon mirrorless adapter
(sold separately) |
| Sony mirrorless with APS-C sensor | Yes |
Sony mirrorless adapter
(sold separately) |
| Canon mirrorless with full frame (42mm) sensor | Yes, but not optimized across the full sensor |
Canon mirrorless adapter
(sold separately) |
| Sony mirrorless with full frame (42mm) sensor | Yes, but not optimized across the full sensor |
Sony mirrorless adapter
(sold separately) |
| DSLR | No | -- |
Unique Optical Design
RASA’s optical design is patented (US 2016/0299331 A1). The design consists of a Schmidt corrector, primary mirror, lens group, and optical window. The lens group contains 4 elements and utilizes rare-earth elements. Unlike many telescopes that only perform well over the visible spectrum (400-700nm), the 8” RASA’s optics are designed to perform over a wider spectral range, from 390-800nm. This allows more of the light emitted from the astronomical object to be sharply focused in the image.
With many imaging systems, adding an extra piece of flat glass such as a filter does not change optical performance. However, that is not the case with super-fast optical systems like the RASA. Our engineers addressed this by designing the RASA with a removeable optical window, so you can maintain peak optical performance if a filter is added or if a camera has its own optical window. Celestron offers a Light Pollution Imaging Filter designed specifically for the 8” 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. This maintains high light transmission through the entire optical system.
When compared with “Hyperstar SCT” systems, the RASA 8 provides better optical performance and field illumination.
| 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 | 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 | Aluminum |
| Optical Tube Length | 628mm (24.7") length | 235mm (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 |
| Included items | M42 camera adapter, C-thread camera adapter, fan battery pack |
| Dovetail | CGE Dovetail Bar |
SKY & TELESCOPE’S HOT PRODUCTS 2019 AWARD
"Incredibly fast optical speeds allow deep-sky imaging with short exposures, opening up a new world of scientific- and recreational-astrophotography possibilities."
Q: Why can’t the Rowe-Ackermann Schmidt Astrograph (RASA) 8 be used visually?
A: The optics produce an image at the front end of the telescope, not the back. Therefore, you cannot look through the RASA 8 with your eyes because your head will block the light from entering the telescope. The RASA 8 is an astrograph designed specifically for deep-sky astronomical imaging.Q: Why was the RASA 8 designed to have a camera mount at the front of the telescope?
A: The RASA 8 optical design uses a prime focus focal plane position in order to obtain its super-fast F/2.0 focal ratio. This necessitates the camera having to be mounted at the front of the astrograph.Q: Won’t the camera block the incoming light?
A: The RASA 8 optical design has its own central obstruction which is caused by the sub-aperture lens assembly at the front of the telescope. The lens assembly has an outer diameter of 93mm. If a camera’s body is smaller than this, it will not block any light from reaching the camera sensor. If the camera body is larger than this, then it will block some of the incoming light. As long as the camera body does not greatly exceed about 120mm diameter, the effect on images is negligible.Q: What cameras can be used with the RASA 8?
A: The RASA 8 can be used with many astronomical CMOS and CCD cameras. It also works well with mirrorless digital cameras. Two key considerations are the size of the camera body (should not exceed about 120mm in diameter), and the camera’s backfocus distance (cannot exceed 25mm). Color or monochrome sensors can be used, although color sensors are easiest to use since the RASA 8 cannot accommodate a filter wheel (see question #7).Q: Why can’t a DSLR be used with the RASA 8?
A: The body size of a DSLR is too large compared to the front aperture of the RASA 8, and therefore blocks too much of the incoming light. Also, the DSLR requires too much backfocus (55mm) for the RASA 8, so the camera sensor cannot be placed at the required location relative to the astrograph. For DSLR imaging, we recommend the RASA 11.Q: What about camera cables in front of the optics?
A: Camera cables which cross the front of the RASA 8 do not block much light and, don’t have a significant effect on images. To minimize any potential diffraction spike around the brightest stars, camera cables can be positioned to cross the aperture in a curved pattern, rather than a straight line.Q: Will I need additional camera adapters for my camera?
A: It depends on what camera you are using. For cameras with a C-mount, no additional adapters are required. For cameras which mount with a 42mm thread, a 42mm (or T-thread) spacer ring to place the camera sensor at the proper backfocus distance relative to the optics will be needed. (Note: With the included 42mm camera adapter, the backfocus distance required is 25mm. So, subtract the backfocus distance specification for your camera from 25mm, and that is the length of the M42 spacer ring you will need. If the camera has a backfocus distance of more than 25mm, it cannot be used with the RASA 8.) For Sony and Canon mirrorless cameras, Celestron offers optional camera adapters. For other cameras, a custom camera adapter will be needed.Q: What is the difference between the image circle and the useable field?
A: The image circle is the diameter at the focal plane (i.e. where the camera sensor is positioned) which the astrograph’s performance was optimized for. The useable field is the diameter at the focal plane where the performance of the astrograph is excellent. Most astrographs only mention the useable field in their specifications.Q: What if my camera’s sensor is larger than the useable field?
A: The RASA 8 has a useable field of 32mm. A sensor with a diagonal size larger than that, such as a full-frame mirrorless camera, can be used, but there will be some drop off in optical performance and field illumination in the corners of the image. This may require cropping during image processing.Q: Can filters be used with the RASA 8?
A: The RASA 8 has a removeable optical window which can be replaced with a filter. Currently, Celestron offers a Light Pollution Reduction Filter for the RASA 8. Filter “sliders” offered by some manufacturers may also work with some cameras. A filter wheel cannot be used, since the filter wheel would have to mount in front of the optics and would block too much of the incoming light.Q: Why does the RASA 8 have a removeable optical window?
A: With such a fast optical system, you cannot add a filter into the light path without adversely affecting the optical performance. With a removeable optical window, you can replace the window with a filter with no loss of performance.Q: Why is the fast focal ratio (F/2.0) of the RASA 8 such a big deal?
A: Because it allows much shorter exposures to be used to capture detail in fainter astronomical objects. This makes getting good images much easier and quicker. With a sensitive high-speed camera along with live image stacking software, you can see images in “real-time” on your computer screen.Q: What mounts can be used with the RASA 8?
A: Any mount which can accept a CGE (or Losmandy D) dovetail bar and can handle at least 20 lbs. The RASA 8 weighs 17 lbs, and you’ll also need to account for the weight of your camera and any other accessories.
Q: Will I need to collimate (i.e. align) the optics?
A: The optics are aligned at the factory, and should not normally need adjustment. However, there are screws which adjust the tilt of the lens assembly should collimation adjustment ever be needed.
Q: What is focus shift, and how does the Ultra-Stable Focus System (USFS) help to minimize it?
A: Focus shift is when the image in your camera moves a little bit when focusing. This can make critical focusing more challenging. The RASA 8 focuses by moving the primary mirror inward-and-outward. If the mirror moves at all laterally, then focus shift will result. The USFS works by using pre-loaded precision ball bearings on the focus tube which the primary mirror rides on. This constrains any lateral motion of the primary mirror and minimizes focus shift. This also helps prevent any unwanted lateral motion of the primary mirror (also known as “mirror flop”) as the astrograph is pointed to different positions in the night sky.
Q: What is the extended spectral range (400-800 nm) and what is the benefit?
A: Most telescopes are designed to perform well over the visual spectrum (i.e 400-700nm). The RASA 8 optics were designed to perform over a wider spectral range, from 400-800nm. This means that light from 700nm-800nm will be well focused in the RASA 8, allowing more of the light emitted from the astronomical object to be sharply focused in the image. For cameras which have spectral response in the 700-800nm range, you’ll get brighter and sharper images and won’t necessarily need to use an IR-cut filter.
Q: What else might be needed with the RASA 8?
A: A finderscope can be useful for visually finding objects or for initial alignment of your computerized mount with the night sky. The RASA 8 has mounting holes for a finderscope. If doing longer exposures, you may want to consider using a guide scope and autoguider in order to provide the best tracking performance with your mount. For convenient mounting of a guide scope, Celestron offers a CGE dovetail accessory mounting bar which connects to the top of the RASA 8 and allows easy installation of guide scope rings. Perhaps the most useful accessory is a focus motor, this permits focusing from the computer which is controlling the camera and/or mount. A focus motor which is compatible with the RASA 8 will soon be introduced by Celestron.
Q: What is the purpose of the integrated air-cooling system?
A: The RASA 8 will perform the best when its optics have reached thermal equilibrium with the outside air. The cooling system uses a fan and vents to pull air through the astrograph and around the primary mirror in order to help the RASA 8 reach thermal equilibrium more quickly.
Q: What is the difference between RASA 8 and an 8” SCT or EdgeHD using the Starizona Hyperstar accessory?
A: The RASA 8 provides better optical performance and better field illumination than an 8" SCT or Edge HD with a Hyperstar accessory. The Hyperstar accessory provides great flexibility for an SCT or EdgeHD optical system, as it allows the telescope to be used at two different focal lengths. When imaging at F/2.0 however, it cannot provide the performance of the RASA 8.
Q: What about dew?
A: Just like any telescope design which uses a lens at the front of the telescope, the RASA 8 Schmidt corrector lens can be susceptible to dew under certain environmental conditions. To prevent dew when the outside temperature drops below the dew point, we recommend using a dew shield or dew heater.
$7,749.00
Capturing impressive deep-sky astroimages is easier than ever with Celestron’s Rowe-Ackermann Schmidt Astrograph (RASA 11) V2, the perfect companion to today’s top DSLR or astronomical CCD cameras. This fast, wide-field f/2.2 system allows for shorter exposure times compared to traditional f/10 astroimaging, without sacrificing resolution. Because shorter sub-exposure times are possible, your equatorial mount won’t need to accurately track over extended periods. The short focal length also lessens equatorial tracking demands. In many cases, autoguiding will not be required.
RASA 11 V2 builds on the legacy of Celestron’s Schmidt Cameras, which allowed astrophotographers to produce images with much shorter exposure times on film in the 1970s.
Today, with CCD sensor sizes as large as film or larger, the RASA 11 V2 offers a 43.3mm optimized image circle to capture pinpoint stars on the largest imaging chips. Optical performance for huge sensors with diagonals of up to 52mm wide is still excellent.
Combine this large image circle with a focal length of just 620mm and you have an instrument suitable for wide-field imaging, creating huge mosaics of the night sky, surveying, 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 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.
| OPTICAL TUBE INFO: | |
|---|---|
| Optical Design | Rowe-Ackermann Schmidt Astrograph |
| Aperture | 279mm (11") |
| Focal Length | 620mm (24.4") |
| Focal Ratio | f/2.2 |
| Central obstruction diameter | 114mm (4.48") (41% of aperture diameter) |
| Light Gathering Power (Compared to human eye) | 1588x |
| Resolution (Rayleigh) | 0.49 arc seconds |
| Resolution (Dawes) | 0.41 arc seconds |
| Image Circle | 43.3mm (1.7") Ø , 4.0° |
| Useable field | 52mm (2.04") Ø , 4.8° only minimal performance loss at edge of FOV |
| Wavelength range | 400 - 700 nm |
| Spot size | < 4.4 μm RMS across FOV |
| Optical Coatings | StarBright XLT |
| Off-axis Illumination | 83% at 21mm (.82") off-axis |
| Optical Window | 68mm (2.67") Ø |
| Back focus with included camera adapter | 55mm (2.16") |
| Back focus from top of threaded collar | 72.8mm (2.86") |
| Optical Tube | Aluminum |
| Optical Tube Length | 838.2mm (33") |
| Optical Tube Diameter | 330.2mm (13") |
| Focuser | Ultra-Stable Focus System |
| Finderscope | Not included |
| Optical Tube Weight | 43 lbs (19.5 kg) |
| Other Features | Ventilation fan, dual dovetail mounting bars |
| Included items | 42mm (1.65") T-thread camera adapter | 48mm (1.89") camera adapter | Dust cover | Fan battery pack |
| Dovetail | CGE Dovetail Bar |
The night sky, at f/2.2.
The smallest Rowe-Ackermann Schmidt Astrograph ever built. Ultra-fast prime-focus optics, sub-arcsecond resolution and 3.8 kg of grab-and-go portability for serious deep-sky astrophotography, anywhere.
Professional optics. In a body you can carry with one hand.
Patented Rowe-Ackermann Schmidt architecture.
The RASA places the camera at prime focus, the same position used by professional wide-field survey telescopes. No secondary mirror, no Barlow, no lost light. More photons reach your sensor, in less time.
Since RASA technology debuted in 2014, defence contractors, professional researchers and governments have relied on it for space surveillance and satellite tracking. The RASA 6 delivers that same proven design in a portable package.
- Schmidt corrector plate and primary mirror minimise optical aberrations across the field
- Three-element rare-earth glass lens group ensures sharp, flat focus edge-to-edge
- Spot size under 1.5 μm RMS across the full image circle
NGC 6888. The Crescent Nebula.
Captured with the RASA 6 and an astronomical CMOS camera. Short sub-exposures stack into stunning images in a fraction of the time needed by slower instruments.
Four reasons it’s unlike anything else in its class.
Speed, resolution, portability and field of view, all engineered into one compact prime-focus astrograph.
Lightning-fast astrophotography at f/2.2.
The RASA 6’s blazing focal ratio dramatically shortens sub-exposure times. Faint deep-sky objects that would take hours with a typical refractor can be captured in a fraction of that time. Paired with live-stacking software, bright detailed images appear on your screen in just minutes. In many conditions you can image without an autoguider, simplifying your entire setup.
Sub-arcsecond potential.
Despite its compact size the 152 mm aperture delivers a Dawes resolution of 0.76 arc seconds. Pair it with a high-resolution CMOS camera in steady seeing and you will resolve fine structure in galaxies, nebulae and star clusters that smaller instruments cannot touch. The flat field means stars stay sharp from the centre all the way to the corner of the sensor.
Grab-and-go, genuinely.
At 3.8 kg the RASA 6 is light enough to carry with one hand and fits in a bag alongside your mount. The CG-5 dovetail means it drops straight onto most mid-range tracking mounts without adapters. Chase dark skies without compromising on optical performance. This is the astrograph you will actually take with you.
Wide field without sacrifice.
The RASA 6 is designed for sensors up to 22 mm diagonal, delivering a useable field of 3.76°. Wide enough to frame the Orion Nebula, the Pleiades and large emission nebulae in a single shot. Off-axis illumination of 91% at 8 mm means the field stays bright from edge to edge, reducing processing time on flats and vignette correction.
StarBright XLT. Maximum light throughput.
Every refractive and reflective surface is treated with Celestron’s proprietary StarBright XLT multi-layer coating. The result is exceptional light transmission and superior field illumination across the full wavelength range from 400 to 700 nm.
The RASA design outperforms a Schmidt-Cassegrain in Fastar-style configuration for field illumination. Less vignette, less processing, more imaging.
M42. The Orion Nebula.
IMX183C colour CMOS camera. 60 × 2 min exposures plus 20 × 15 sec exposures for the bright core. The wide field and fast optics of the RASA 6 capture the full extent of the nebula in a single frame.
Everything the modern astroimager needs, integrated.
A filter drawer, a cooling fan, a camera adapter and a CG-5 dovetail. Ready to image, straight out of the box.
1.25″ and 2″ filters. Without slowing you down.
The built-in filter drawer accepts both 1.25″ and 2″ filters. A removable 2″ clear optical window ships as standard. Unlike many fast astrographs, swapping in a filter adds no extra glass to the optical path, so f/2.2 performance is fully preserved.
Thermal equilibrium, fast.
The integrated 12V DC MagLev fan pulls air through mesh vents to rapidly cool the optical system to ambient temperature. Sharper stars and better images from the moment you start. The fan battery pack is included.
Plug a CMOS camera straight in.
The included M42 T-thread camera adapter attaches most popular astronomical CMOS cameras directly to the RASA 6 without extension tubes. The 42 mm clear aperture comfortably accommodates sensors up to 22 mm diagonal. Back focus with the included adapter is 17.5 mm.
Mount-ready, no adapters.
The CG-5 dovetail bar is compatible with a wide range of tracking mounts straight out of the box. No adapters, no Vixen-to-Losmandy conversions. Ready to image as soon as you saddle up. For maximum performance, add the optional Celestron Focus Motor for electronic focus control.
Results from the RASA 6.
Sample images taken with the RASA 6 and an IMX183C colour CMOS camera at f/2.2.
Highlights.
Everything that makes the RASA 6 the most portable serious astrograph in its class.
152 mm (5.98″) aperture, 335 mm focal length, f/2.2 prime focus
Patented Rowe-Ackermann Schmidt prime-focus astrograph optical design
StarBright XLT multi-layer coatings on every refractive and reflective surface
91% off-axis illumination at 8 mm and 472× light-gathering vs the eye
Useable field of 3.76° for sensors up to 22 mm diagonal
Built-in 1.25″ / 2″ filter drawer with included clear optical window
Integrated 12 V DC MagLev cooling fan with battery pack
3.8 kg optical tube with CG-5 dovetail for fast mount setup
Celestron RASA 6.
Complete technical data for your imaging setup planning.
| Optical Tube | |
| Optical design | Rowe-Ackermann Schmidt Astrograph |
| Aperture | 152 mm (5.98″) |
| Focal length | 335 mm (13.18″) |
| Focal ratio | f/2.2 |
| Optical coatings | StarBright XLT (all refractive and reflective surfaces) |
| Tube material | Aluminium |
| Tube length | 609.6 mm (24″) |
| Tube diameter | 177.8 mm (7″) |
| Weight | 3.8 kg (8.4 lb) |
| Dovetail | CG-5 dovetail bar |
| Focuser | Standard Schmidt-Cassegrain focuser |
| Optical Performance | |
| Central obstruction | 77 mm (3.03″) - 46% of aperture diameter |
| Light-gathering power | 472× vs the human eye |
| Resolution (Rayleigh) | 0.91 arc seconds |
| Resolution (Dawes) | 0.76 arc seconds |
| Spot size | < 1.5 μm RMS across the full image circle |
| Off-axis illumination | 91% at 8 mm (0.31″) off-axis |
| Wavelength range | 400–700 nm |
| Field of View & Camera Interface | |
| Image circle | 16 mm (0.63″) Ø, 2.74° |
| Useable field | 22 mm (0.86″) Ø, 3.76° (minimal performance loss at edge) |
| Camera mounting threads | M42 |
| Back focus (with adapter) | 17.5 mm (0.69″) |
| Filter System | |
| Filter drawer | Accepts 2″ format filters, includes 1.25″ adapter |
| Clear filter included | 2″ AR-coated optical window, 2 mm glass |
| Cooling & Electronics | |
| Cooling fan | 12 V DC MagLev |
| Fan power | Fan battery pack (included) |
| In the Box | |
| Included items | M42 (42 mm T-thread) camera adapter, fan battery pack, filter drawer with 2″ clear filter |
Professional optics. Portable by design.
The same prime-focus optical technology trusted by defence contractors and professional researchers, now in a grab-and-go package built for serious Australian astrophotographers. Backed by Bintel’s 40 years of expert optics support.
$31,499.00
The Rowe-Ackermann Schmidt Astrograph (Celestron RASA 36), is a cost-effective optical system for space surveillance, Space Situational Awareness (SSA), other scientific applications, and advanced wide field astroimaging. It offers unprecedented value in aperture, speed, field of view, and optical performance. The RASA design has a convenient external prime-focus image capture location with a flat focal plane, providing small spot sizes to the edge of a wide field. The result is images free of optical defects like field curvature, off-axis coma, and astigmatism.
The 36 cm aperture version is the largest RASA Celestron manufactures; it is the biggest and fastest (f/2.2) optical instrument of its kind available off-the-shelf. Unlike most telescopes, which only focus visible light (400-700 nm), the RASA 36 cm focuses an extended spectral range (400-900 nm), allowing a brighter signal to be detected by a camera sensor. The RASA 36 cm also features a redesigned focus system, which ensures easy and stable focusing.
RASA 36 c sample back-focus distance (77.5 mm) accommodates a wide variety of imaging sensors. A custom camera adapter can be added for a field of view up to 4.4 degrees.
Important freight requirement RASA 36 is a professional-caliber, high-precision instrument. It is manufactured and aligned to an exacting standard to provide exceptional optical performance. The telescope has been packaged to ensure it retains alignment and resulting performance during transport. However, due to the weight, size, and known stresses of shipping via parcel service, Celestron has determined that the ideal transport is a palletized delivery via LTL truck freight. For all Australian deliveries, Celestron will ship via this method. Please contact us for further freight costs
| OPTICAL TUBE INFO: | |
|---|---|
| Optical Design | Rowe-Ackermann Schmidt Astrograph |
| Aperture | 355.6mm (14") |
| Focal Length | 790mm (31.1") |
| Focal Ratio | f/2.2 |
| Central obstruction diameter | 158mm (6.22")(44% of aperture diameter) |
| Light Gathering Power (Compared to human eye) | 2581X |
| Resolution (Rayleigh) | 0.39 arc seconds |
| Resolution (Dawes) | 0.36 arc seconds |
| Image circle | 60.1mm (2.36") Ø, 4.4° |
| Useable field | 70mm (2.75") Ø, 5.1°, only minimal performance loss at edge of FOV |
| Wavelength range | 400 – 900 nm |
| Spot size | < 6.3 μm RMS across FOV |
| Optical coatings | Enhanced aluminum, XLT multi-coatings used throughout |
| Off-axis Illumination | 83% at 30mm (1.18") off-axis |
| Optical window | 104mm (4.09") Ø |
| Back focus with included camera adapter | 55mm (2.16") |
| Back focus from top of threaded collar | 77.5mm (3.05") |
| Optical Tube | Aluminum |
| Optical Tube Length | 1079.5mm (42.5") |
| Optical Tube Diameter | 406.4mm (16") |
| Focuser | New focuser design, minimizes focus shift |
| Finderscope | Not included |
| Optical Tube Weight | 75 lbs (34.02 kg) |
| Other features | Ventilation fan, dual dovetail mounting bars |
| Included items | 48mm (1.89") camera adapter, fan battery pack |
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