Celestron EdgeHD 11 Optical Tube Assembly

• 11" (280mm) aperture
• f/10 focal ratio
• 2800mm effective focal length
• Aplanatic Schmidt-Cassegrain optical design
• EdgeHD field-flattener aplanatic design eliminates spherical aberration, field curvature, and off-axis star coma to improve resolution, sharpness, and clarity across the entire field of view, especially at the edges
• Diffraction-limited SCHOTT glass reduces internal light loss to improve color, clarity, and sharpness
• StarBright XLT optical coatings
• Flexible tension clutches hold the primary mirror in place to reduce image shift without putting any force or pressure on the mirror assembly, keeping subjects centered
• Internal mirror locks prevent accidental adjustment to focus—important during long-exposure astrophotography
• Integrated 95-micron mesh filter allows hot air to be released from behind the primary mirror without dust getting in, to prevent mirror distortion due to uneven surface temperatures
• Resolution: 0.5 arcsec (Rayleigh); 0.42 arcsec (Dawes)
• Secondary mirror obstruction: 3.75" (95 mm); 34% by diameter; 12% by area

• Maximizes light transmission through optical path
• Improves color rendition, contrast, sharpness, resolution, and brightness
• Broadband system provides flat wavelength transmission across the entire visual spectrum
• Multi-layer mirror coatings with layers of aluminum, SiO2 (quartz), and TiO2 (titanium dioxide)
• Multi-layer anti-reflective corrector plate coatings with layers of MgF2 (magnesium fluoride) and HfO2 (hafnium dioxide); hafnium has a wider band-pass than the commonly used titanium
• High-transmission water white glass corrector plate limits light loss due to internal absorption

• OTA only; mount and tripod required for proper use
• Large CGE (Losmandy-style) dovetail plate

• Standard Schmidt-Cassegrain telescope (SCT) threads
• 2" eyepiece/accessory holder
• Use for prime focus or projection astrophotography with optional adapters

Eyepiece:

• Luminos-series wide-angle
• 82° field of view
• 2"-diameter barrel
• Accepts most 2" eyepiece filters
• 23mm focal length yields 122x power
• Parfocal with all Luminos eyepieces, allowing it to be changed out with other Luminos eyepieces without having to adjust the focus
• Retractable eyecup for use with or without eyewear

Reducer adapter:

• 2"-to-1.25" reducer adapter allows the use of smaller eyepieces and accessories in visual back or diagonal

Diagonal:

• 90° angle puts head in comfortable viewing position
• Threaded for direct connection to OTA without the need for the visual back
• 2" eyepiece/accessory holder
• Star diagonal corrects image horizontally, but not vertically

Finderscope:

• Low 9x magnification preserves wide field of view to more easily find alignment or guide stars
• Large 50mm aperture helps to see dimmer objects and stars for easier star-hopping navigation

In the Box

• Celestron EdgeHD 11" f/10 Aplanatic Schmidt-Cassegrain Telescope (OTA Only)
• 9x50 Finderscope
• 2" 90° Star Diagonal
• 1.25" Eyepiece Reducer Adapter
• Limited 2-Year Warranty