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iOptron Photron 200mm f/8 Ritchey-Chretien Catadioptric Telescope (OTA Only) IN STOCK - 1 left

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Click here   https://www.buytelescopes.com/ioptron-photron-200mm-f8-ritchey-chretien-catadioptric-telescope-ota-only-176097  

Utilizing the same hyperbolic primary and secondary mirror design used in the Hubble Space Telescope, the Keck telescopes, and the ESO Very Large Telescope, the iOptron Photron 200mm f/8 Ritchey-Chretien Catadioptric Telescope represents the medium-aperture in the series and is ideally suited for both star-gazing and astrophotography. Despite its larger mirror and long focal length, it delivers views that are free from off-axis comas, or spherical and chromatic aberrations, yet maintains a highly-portable form factor. The low thermal-expansion quartz primary and secondary mirrors are treated with highly-reflective dielectric coatings that, when combined with internal knife-edge baffles, limit distortion as the mirrors heat while limiting stray internal light and maximizing light transmission. All this translates to bright and sharp high-contrast images with accurate color fidelity across the entire distortion-free field of view.

 

Unlike other catadioptric designs, this RCT has a fixed primary mirror to eliminate the image-shift that is common with conventional configurations that move the mirror forward and back to focus the image. With the primary mirror fixed in-place, iOptron installed a precise two-speed Crayford-style focuser with a 10:1 reducer that allows for fast coarse and precise fine focusing without the backlash that occurs in the more common rack-and-pinion design — essential for astrophotography or splitting objects that are close together, like binary stars. To ensure complete coverage of today's imaging sensors, the focuser has a 2" drawtube and comes with three extension rings to help users achieve the proper back-focus distance. The larger drawtube also allows the use of large eyepieces which generally have longer eye reliefs to make visual observations much more comfortable; and comes with a 1.25" reducer to enable the smaller and more common-sized eyepieces and accessories to be easily used.

Intended for those who have a reliable support system, iOptron offers the RCT here as an OTA-only option. A long Losmandy-style dovetail plate is factory-installed to make it compatible with a wide variety of heavier-duty alt-azimuth, equatorial, and GoTo mounts that can carry a minimum payload of at least 18 pounds. To make adding accessories, such as a smaller guide scope, or to piggy-back imaging or DSLR cameras for wide-field photography, a smaller Vixen-style dovetail plate is also pre-installed on the top of the OTA.

Optical Tube Assembly
  • Large 200mm (7.9") clear aperture provides performance while keeping the OTA portable; 95mm secondary mirror
  • Long 1624mm focal length provides a moderate magnification potential and focal ratio for astrophotography
  • Moderate f/8 focal ratio allows for shorter exposure times for imaging than slower OTAs
  • Ritchey-Chrétien catadioptric design delivers views free from off-axis comas, or spherical and chromatic aberrations
  • Low thermal-expansion quartz primary and secondary mirrors limit distortion as the mirrors heat
  • Highly reflective dielectric mirror coatings transmit more than 99% of incoming light to ensure bright and clear images
  • Ten internal knife-edge baffles diminish stray light, improving contrast for visual and imaging applications
  • Fixed-position primary mirror eliminates image-shift common in other catadioptric designs
  • Resolution: 0.58 arcsec
  • 10:1 dual-speed linear-bearing Crayford focuser allows for fast coarse and precise fine focus without backlash for tack-sharp focusing; with tension-adjustment knob and drawtube lock-knob
  • Large 2" drawtube ensures complete coverage of imaging sensors to eliminate or limit vignetting; and allows the use of larger eyepieces to make viewing easier and more comfortable; with etched scale in inches and millimeters for precise repeatability
  • Factory-installed mounting plate for user-supplied finder
Mounting
  • Optical tube assembly only - mount and tripod required for proper use
  • Long Losmandy-style dovetail plate is compatible with the most popular size saddles on alt-az, equatorial, and GoTo mounts
  • Weight: 18 pounds
  • Secondary upper Vixen-style dovetail plate enables easy mounting of smaller guide-scopes or to piggy-back imaging or DSLR cameras for wide-field astrophotography
Included Accessories Reducer Adapter:
  • 2"-to-1.25" reducer allows the use of the smaller, more common-sized accessories and eyepieces in the larger focuser drawtube
Extension Rings:
  • Three focuser rings allow for increased back-focus distance to ensure the focal plane properly lands on imaging sensors or specialized visual equipment
  • Rings can be used one at a time, or stacked as needed
  • Simple screw-together design requires no tools or permanent modification
  • Includes two (2) 1" tubes and one (1) 2" tube