8" RASA8 Optical Tube Assembly
$2,079.00
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8" RASA8 Optical Tube Assembly
$2,079.00
Ultra-Fast Optics
Superb f/2.0 focal ratio
Compact Design
Lightweight 17 pound body
Stable Focuser
Linear ball bearing mechanism
Active Cooling
Integrated MagLev fan system
Broad Spectrum
Optimized 390 to 800nm
StarBright XLT
Maximum optical light transmission
Deep Sky Astrophotography RedefinedCapture stunning wide-field cosmos images
The Celestron 8" RASA 8 Optical Tube Assembly is an ultra-fast f/2.0 prime focus astrograph designed for capturing breathtaking deep-sky celestial images in seconds. Engineered specifically for modern astronomical CMOS and mirrorless cameras, this portable astrograph telescope eliminates the need for long exposure tracking and complex autoguiding. Weighing just 17 lbs, the Celestron 8" RASA allows astrophotographers to transport a high-performance optical tube directly to dark sky locations.
Advanced Optical Design For AstroimagersRazor sharp images across the field
Designed exclusively for deep-sky imaging, the Celestron 8" RASA 8 Optical Tube Assembly utilizes a patented 4-element rare-earth lens system paired with a Schmidt corrector to eliminate field curvature, coma, astigmatism, and chromatic aberration across an entire APS-C sensor. Featuring Celestron's StarBright XLT coatings and enhanced aluminum primary mirror coatings, light transmission reaches up to 97.4% for unrivaled contrast and detail. The innovative Ultra-Stable Focus System incorporates precision linear ball bearings to virtually eliminate image shift during focusing or tracking. Coupled with an integrated 12V DC MagLev cooling fan and internal filter mount, the Celestron RASA 8 astrograph delivers exceptional wide-field astrophotography performance in a lightweight optical tube assembly.
Technical Specifications SummaryComplete optical tube measurement details
Optical Design
Rowe-Ackermann Schmidt Astrograph
Aperture
203mm / 8 inches
Focal Length
400mm / 15.74 inches
Focal Ratio
f/2.0
Central Obstruction
93mm / 3.66 inches
Light Gathering Power
843x human eye
Resolution (Rayleigh)
0.68 arc seconds
Resolution (Dawes)
0.57 arc seconds
Image Circle
22mm Ø / 3.15 degrees
Usable Field
32mm Ø / 4.6 degrees
Wavelength Range
390 - 800 nm
Optical Coatings
StarBright XLT
Optical Tube Material
Aluminum
Optical Tube Length
628mm / 24.7 inches
Optical Tube Weight
17 lbs / 7.7 kg
Dovetail
CGE Dovetail Bar
Focuser
Ultra-Stable Focusing System
Back Focus
25mm with included adapter / 29mm from collar
Included Items
M42 camera adapter, C-thread adapter, fan battery pack
Precision Engineering HighlightsKey capabilities of the RASA astrograph
Optical SystemFast f/2.0 focal ratio prime focus system
Field PerformanceFlat field free of chromatic aberrations across APS-C sensors
Focus SystemUltra-Stable precision linear ball bearing mechanism
Cooling SystemIntegrated 12V DC MagLev air-cooling fan with dust filter
Spectral RangeExtended 390-800 nm optical performance for sharp focus
Filter MountRemovable internal optical window and filter mount
Mount CompatibilitySturdy CGE dovetail mounting bar included
CoatingsStarBright XLT optical coatings for maximum light transmission
Frequently Asked QuestionsEverything you need to know
Can I use a DSLR camera with the Celestron 8" RASA 8 Optical Tube Assembly?
No, the Celestron 8" RASA 8 Optical Tube Assembly is optimized specifically for astronomical CMOS cameras, smaller CCD cameras, and mirrorless cameras. Standard DSLR camera bodies are physically too large in diameter and block too much incoming light.
Can the Celestron 8" RASA 8 Optical Tube Assembly be used for visual observing with an eyepiece?
No, the Celestron 8" RASA 8 is strictly an astrograph designed for camera imaging only. Because the focal plane is located at the front prime focus, it cannot accommodate traditional visual eyepieces.
What mount is compatible with the Celestron 8" RASA 8 Optical Tube Assembly?
The Celestron 8" RASA 8 Optical Tube Assembly features a standard CGE dovetail mounting bar, making it compatible with CGE/Losmandy-style equatorial mounts. Weighing only 17 pounds, it easily pairs with a wide variety of medium-capacity computerized equatorial mounts.
Is autoguiding required when imaging with the Celestron 8" RASA 8 Optical Tube Assembly?
Due to its extremely fast f/2.0 focal ratio and short 400mm focal length, short exposure times can capture faint deep-sky details, which often eliminates the need for an autoguider.