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RC20 — 20-Inch Ritchey-Chrétien Optical Tube Assembly

SKU: 200125Q Categories: , ,

$57,500.00

The 20-Inch Ritchey-Chrétien (RC20) from PlaneWave Instruments exemplifies the blend of advanced engineering and high-performance design tailored for professional astronomers and astrophotographers. With its Ritchey-Chrétien optical design, the RC20 is ideal for delivering sharp, high-contrast images for a variety of demanding observational and scientific applications.

*Price excludes shipping and crating. See our crating and pricing policy for full details.

Key Features Overview

The RC20 is notable for its superior specifications and features:

  • 20-inch (508 mm) aperture
  • Ritchey-Chrétien (RC) optical design
  • 3556 mm focal length
  • f/7 focal ratio
  • 147 mm back focus from racked in focuser
  • Dual carbon-fiber truss design
  • Lightweight and robust construction
About the RC20 — 20-Inch Ritchey-Chrétien Optical Tube Assembly

RC20’s Key Features

Large Aperture and Ritchey-Chrétien Optics

The RC20 features a purely reflective Ritchey-Chrétien optical system, which includes high-quality mirrors with enhanced coatings. This setup minimizes chromatic aberration and ensures excellent light throughput, providing superb image fidelity and contrast. This optical design shines when making observations, primarily on-axis, and wide-field imaging is not a concern.

Mechanical Structure

Constructed from lightweight yet durable materials, including a dual carbon-fiber truss design, the 20-inch Ritchey-Chrétien ensures structural integrity and reduces the overall weight. This makes it easier to handle and mount on various telescope mounts.

Thermal Management

Equipped with three cooling fans at the back of the telescope, the RC20 achieves thermal equilibrium quickly. This feature helps to reduce air turbulence inside the telescope tube, minimizing thermal distortions and maintaining optimal imaging conditions.

Application-Specific Benefits

Astrophotography

The large aperture and precision optics of the 20-Inch Ritchey-Chrétien enable astrophotographers to capture detailed and crisp images of celestial phenomena, making it an excellent tool for capturing faint galaxies, nebulae, and star clusters.

Astronomy Research

With its reliable performance and detailed imaging capabilities, the 20-inch Ritchey-Chrétien is a valuable asset for universities and research observatories that engage in complex studies such as stellar classification, photometric research, and other scientific investigations.

Specifications

RC20 — 20-Inch Ritchey-Chrétien Optical Tube Assembly

OPTICAL SYSTEMS
SECONDARY MIRROR
PRIMARY MIRROR
included items
Aperture 508 mm (20")
Focal Length 3556 mm (140")
Focal Ratio f/7
Central Obstruction 39% of the Primary Mirror Diameter
Back Focus from Racked in Focuser 147 mm (5.8")
Weight 140 lbs (63.5 kg)
OTA Length 1194 mm (47")
Upper Cage Carbon Fiber Truss
Lower Cage Carbon Fiber Truss with Carbon Fiber Light Shroud
Diameter 191mm (7.5")
Material Fused silica
Shape Hyperbolic
Coating Enhanced Aluminum – 96%
Optical Diameter 508 mm (20")
Outer Diameter 521 mm (20.5")
Shape Hyperbolic
Material Enhanced Aluminum – 96%
Coating Fused Silica
Included Items Heating Elements for Dew Prevention - The heating pads on the primary and secondary mirror require the 600195 Delta-T controller sold separately
OTA Cover - To protect the primary mirror and inside of the optical tube
Flashdrive - Contains software and instructions for collimation and spacing the primary to secondary mirror
Wrench Set (5812A35) - Standard hex wrenches (European orders only)

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