{"product_id":"celestron-8-rowe-ackermann-schmidt-astrograph-rasa-8-optical-tube-assembly-cge-dovetail","title":"Celestron 8” Rowe-Ackermann Schmidt Astrograph (RASA 8) Optical Tube Assembly (CGE Dovetail)","description":"\u003cul\u003e\n\u003cli\u003eFlat field free of optical aberrations like field curvature, coma, astigmatism and chromatic aberration across an entire APS-C sensor.\u003c\/li\u003e\n\u003cli\u003eUnlike 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.\u003c\/li\u003e\n\u003cli\u003eUltra-Stable Focus System – precision linear ball bearing virtually eliminates image shift.\u003c\/li\u003e\n\u003cli\u003eIntegrated air cooling system –12V DC MagLev fan reduces cooldown time and provides optimal air flow while filtering out dust.\u003c\/li\u003e\n\u003cli\u003eInternal filter mount – seamlessly accommodates a Light Pollution Imaging Filter into the optical path.\u003c\/li\u003e\n\u003cli\u003eCGE dovetail mounting rail.\u003c\/li\u003e\n\u003cli\u003ePerforms over a wider spectral range than most telescopes, from 400nm – 800nm, so more of the light passing through the astrograph is in sharp focus.\u003c\/li\u003e\n\u003cli\u003e\n\u003cp\u003eCapture 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.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003e \u003c\/strong\u003e\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eRASA Performance Made for Everyone\u003c\/strong\u003e\u003c\/p\u003e\n\u003cp\u003eThe 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.\u003c\/p\u003e\n\u003cp\u003eThe 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.\u003c\/p\u003e\n\u003cp\u003ePurely 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.\u003c\/p\u003e\n\u003cp\u003e \u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eShorter Exposure Times and Virtual “Real-Time” Observing\u003c\/strong\u003e\u003c\/p\u003e\n\u003cp\u003eSince 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.\u003c\/p\u003e\n\u003cp\u003eBecause 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.\u003c\/p\u003e\n\u003cp\u003e \u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eUltra-Stable Focus System\u003c\/strong\u003e\u003c\/p\u003e\n\u003cp\u003eWith the launch of the 8” RASA, Celestron is unveiled 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.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003e \u003c\/strong\u003e\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eBuilt for Today’s Latest Cameras\u003c\/strong\u003e\u003c\/p\u003e\n\u003cp\u003eUnlike 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.\u003c\/p\u003e\n\u003cp\u003e \u003c\/p\u003e\n\u003ctable class=\"compatibility-table\" style=\"width: 100.031%; height: 480.795px;\"\u003e\n\u003ctbody\u003e\n\u003ctr style=\"height: 39.2045px;\"\u003e\n\u003cth style=\"width: 33.8589%; height: 39.2045px;\"\u003eCamera\u003c\/th\u003e\n\u003cth style=\"width: 27.5563%; height: 39.2045px;\"\u003eCompatible with RASA 8?\u003c\/th\u003e\n\u003cth style=\"width: 34.5159%; height: 39.2045px;\"\u003eAdapter required\u003c\/th\u003e\n\u003c\/tr\u003e\n\u003ctr style=\"height: 39.2045px;\"\u003e\n\u003ctd style=\"width: 33.8589%; height: 39.2045px;\"\u003eAstronomical CMOS\/CCD camera with C-mount\u003c\/td\u003e\n\u003ctd style=\"width: 27.5563%; height: 39.2045px;\"\u003eYes\u003c\/td\u003e\n\u003ctd style=\"width: 34.5159%; height: 39.2045px;\"\u003eC-mount adapter (included)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr style=\"height: 58.8068px;\"\u003e\n\u003ctd style=\"width: 33.8589%; height: 58.8068px;\"\u003eAstronomical CMOS\/CCD camera with M42-thread mount\u003c\/td\u003e\n\u003ctd style=\"width: 27.5563%; height: 58.8068px;\"\u003eYes\u003c\/td\u003e\n\u003ctd style=\"width: 34.5159%; height: 58.8068px;\"\u003eM42 adapter (included) with M42 extension tubes (not included)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr style=\"height: 39.2045px;\"\u003e\n\u003ctd style=\"width: 33.8589%; height: 39.2045px;\"\u003eAstronomical CMOS\/CCD camera with other mount\u003c\/td\u003e\n\u003ctd style=\"width: 27.5563%; height: 39.2045px;\"\u003eYes\u003c\/td\u003e\n\u003ctd style=\"width: 34.5159%; height: 39.2045px;\"\u003eCustom camera adapter\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr style=\"height: 71.1932px;\"\u003e\n\u003ctd style=\"width: 33.8589%; height: 71.1932px;\"\u003eCanon mirrorless with APS-C sensor\u003c\/td\u003e\n\u003ctd style=\"width: 27.5563%; height: 71.1932px;\"\u003eYes\u003c\/td\u003e\n\u003ctd style=\"width: 34.5159%; height: 71.1932px;\"\u003e\n\u003cp\u003e\u003ca href=\"https:\/\/www.celestron.com\/products\/camera-adapter-for-canon-mirrorless-rasa-8\" rel=\"noopener noreferrer\" target=\"_blank\"\u003eCanon mirrorless adapter\u003c\/a\u003e\u003c\/p\u003e\n\u003cp\u003e(sold separately)\u003c\/p\u003e\n\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr style=\"height: 71.1932px;\"\u003e\n\u003ctd style=\"width: 33.8589%; height: 71.1932px;\"\u003eSony mirrorless with APS-C sensor\u003c\/td\u003e\n\u003ctd style=\"width: 27.5563%; height: 71.1932px;\"\u003eYes\u003c\/td\u003e\n\u003ctd style=\"width: 34.5159%; height: 71.1932px;\"\u003e\n\u003cp\u003e\u003ca href=\"https:\/\/www.celestron.com\/products\/camera-adapter-for-sony-mirrorless-rasa-8\" rel=\"noopener noreferrer\" target=\"_blank\"\u003eSony mirrorless adapter\u003c\/a\u003e\u003c\/p\u003e\n\u003cp\u003e(sold separately)\u003c\/p\u003e\n\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr style=\"height: 71.1932px;\"\u003e\n\u003ctd style=\"width: 33.8589%; height: 71.1932px;\"\u003eCanon mirrorless with full frame (42mm) sensor\u003c\/td\u003e\n\u003ctd style=\"width: 27.5563%; height: 71.1932px;\"\u003eYes, but not optimized across the full sensor\u003c\/td\u003e\n\u003ctd style=\"width: 34.5159%; height: 71.1932px;\"\u003e\n\u003cp\u003e\u003ca href=\"https:\/\/www.celestron.com\/products\/camera-adapter-for-canon-mirrorless-rasa-8\" rel=\"noopener noreferrer\" target=\"_blank\"\u003eCanon mirrorless adapter\u003c\/a\u003e\u003c\/p\u003e\n\u003cp\u003e(sold separately)\u003c\/p\u003e\n\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr style=\"height: 71.1932px;\"\u003e\n\u003ctd style=\"width: 33.8589%; height: 71.1932px;\"\u003eSony mirrorless with full frame (42mm) sensor\u003c\/td\u003e\n\u003ctd style=\"width: 27.5563%; height: 71.1932px;\"\u003eYes, but not optimized across the full sensor\u003c\/td\u003e\n\u003ctd style=\"width: 34.5159%; height: 71.1932px;\"\u003e\n\u003cp\u003e\u003ca href=\"https:\/\/www.celestron.com\/products\/camera-adapter-for-sony-mirrorless-rasa-8\" rel=\"noopener noreferrer\" target=\"_blank\"\u003eSony mirrorless adapter\u003c\/a\u003e\u003c\/p\u003e\n\u003cp\u003e(sold separately)\u003c\/p\u003e\n\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr style=\"height: 19.6023px;\"\u003e\n\u003ctd style=\"width: 33.8589%; height: 19.6023px;\"\u003eDSLR\u003c\/td\u003e\n\u003ctd style=\"width: 27.5563%; height: 19.6023px;\"\u003eNo\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003c\/tbody\u003e\n\u003c\/table\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003cp\u003e\u003cstrong\u003eUnique Optical Design\u003c\/strong\u003e\u003c\/p\u003e\n\u003cp\u003eRASA’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 400nm – 800nm. This allows more of the light emitted from the astronomical object to be sharply focused in the image.\u003c\/p\u003e\n\u003cp\u003eWith 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.\u003c\/p\u003e\n\u003cp\u003eAll 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.\u003c\/p\u003e\n\u003cp\u003eWhen compared with “Hyperstar SCT” systems, the RASA 8 provides better optical performance and field illumination.\u003c\/p\u003e\n\u003c\/li\u003e\n\u003cli\u003e\n\u003ctable class=\"table-open\" id=\"product-specs-list\"\u003e\n\u003cthead\u003e\n\u003ctr\u003e\n\u003cth\u003eOptical Tube Info:\u003c\/th\u003e\n\u003cth\u003e\u003c\/th\u003e\n\u003c\/tr\u003e\n\u003c\/thead\u003e\n\u003ctbody\u003e\n\u003ctr\u003e\n\u003ctd\u003eOptical Design:\u003c\/td\u003e\n\u003ctd\u003eRowe-Ackermann Schmidt Astrograph\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eAperture:\u003c\/td\u003e\n\u003ctd\u003e203mm (8\")\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eFocal Length:\u003c\/td\u003e\n\u003ctd\u003e400mm (15.74\")\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eFocal Ratio:\u003c\/td\u003e\n\u003ctd\u003ef\/2.0\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eCentral obstruction diameter:\u003c\/td\u003e\n\u003ctd\u003e93mm (3.66\") (46% of aperture diameter)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eLight Gathering Power (Compared to human eye):\u003c\/td\u003e\n\u003ctd\u003e843x\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eResolution (Rayleigh):\u003c\/td\u003e\n\u003ctd\u003e0.68 arc seconds\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eResolution (Dawes):\u003c\/td\u003e\n\u003ctd\u003e0.57 arc seconds\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eImage Circle:\u003c\/td\u003e\n\u003ctd\u003e22mm (.86\") Ø, 3.15°\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eUseable field:\u003c\/td\u003e\n\u003ctd\u003e32mm (1.26\") Ø, 4.6°, only minimal performance loss at edge of FOV\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eWavelength range:\u003c\/td\u003e\n\u003ctd\u003e400 - 800 nm\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eSpot size:\u003c\/td\u003e\n\u003ctd\u003e\u0026lt; 2.3 μm RMS across image circle\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eOptical Coatings:\u003c\/td\u003e\n\u003ctd\u003eStarBright XLT\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eOff-axis Illumination:\u003c\/td\u003e\n\u003ctd\u003e93% at 11mm (.43\") off-axis\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eOptical Window:\u003c\/td\u003e\n\u003ctd\u003e46mm (1.81\") Ø\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eBack focus with included camera adapter:\u003c\/td\u003e\n\u003ctd\u003e25mm (.98\")\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eBack focus from top of threaded collar:\u003c\/td\u003e\n\u003ctd\u003e29mm (1.14\")\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eOptical Tube:\u003c\/td\u003e\n\u003ctd\u003eAluminum\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eOptical Tube Length:\u003c\/td\u003e\n\u003ctd\u003e628mm (24.7\")\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eOptical Tube Diameter:\u003c\/td\u003e\n\u003ctd\u003e235mm (9.3\")\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eFocuser:\u003c\/td\u003e\n\u003ctd\u003ePrecision Bearing System (PBS)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eFinderscope:\u003c\/td\u003e\n\u003ctd\u003eNot included\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eOptical Tube Weight:\u003c\/td\u003e\n\u003ctd\u003e17 lbs (7.7 kg)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eOther Features:\u003c\/td\u003e\n\u003ctd\u003eAir-cooling system, integrated filter mount\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eIncluded items:\u003c\/td\u003e\n\u003ctd\u003e42mm (1.65\") T-thread camera adapter | C-thread camera adapter | Fan battery pack\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eDovetail:\u003c\/td\u003e\n\u003ctd\u003eCGE Dovetail Bar\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eSolar Warning\u003c\/td\u003e\n\u003ctd class=\"solar-warning\"\u003e\n\u003cul class=\"solar-warning-text\"\u003e\n\u003cli\u003eNever look directly at the Sun with the naked eye or with an optic (unless you have the proper solar filter). Permanent and irreversible eye damage may result.\u003c\/li\u003e\n\u003cli\u003eNever use your optic to project an image of the Sun onto any surface. Internal heat build-up can damage the optic and any accessories attached to it.\u003c\/li\u003e\n\u003cli\u003eNever leave your optic unsupervised. Make sure an adult who is familiar with the correct operating procedures is with your optic at all times, especially when children are present.\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003c\/tbody\u003e\n\u003c\/table\u003e\n\u003c\/li\u003e\n\u003c\/ul\u003e","brand":"Celestron","offers":[{"title":"Default Title","offer_id":51140300243258,"sku":"","price":249999.0,"currency_code":"INR","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0691\/1456\/0826\/files\/rasa1.webp?v=1744444057","url":"https:\/\/edisla.in\/products\/celestron-8-rowe-ackermann-schmidt-astrograph-rasa-8-optical-tube-assembly-cge-dovetail","provider":"EDISLA","version":"1.0","type":"link"}