24 inch Ritchey-Chrétien Optical Tube Assembly


24 inch Ritchey-Chrétien Optical Tube Assembly

Regular price
$ 86,500.00
Sale price
$ 86,500.00
Unit price

This item is out of stock but you can place an order now and we’ll ship when it becomes available.

Shipping on this item will be quoted and billed separately. We will reach out to you to estimate a lead time and make shipping arrangements.


Delta-T Ready – Now the RC24 comes standard with built-in dew heaters for both primary and secondary mirror. A $550 value!

Introducing the PlaneWave Instruments PW24-RC, a 24 inch (0.61 m) telescope with Ritchey-Chrétien optics. PlaneWave’s CDK astrographs have become the telescopes of choice for universities, industry, and astrophotographers around the world, and now PlaneWave offers the PW-RC series to meet the custom needs of the scientific community.

The PW24-RC in its native format (no field flattening lenses) uses only a primary and secondary mirror with reflective coatings. This can be useful when making observations primarily on-axis and wide field imaging is not a concern.


Ritchey-Chrétien (RC) Optics Fused silica RC optics made by PlaneWave for excellent on-axis performance using only a hyperbolic primary and secondary mirror with no refractive optics in the light path.  
Carbon Fiber Truss Design Minimizes thermal expansion to prevent focus shift with changes in temperature.
Dovetail expansion joint Accommodates the difference in thermal expansion between carbon fiber and aluminum. The expansion joint allows the aluminum dovetail to expand and contract without stressing the carbon fiber lower truss.  
Cooling Fans Three cooling fans blow out the back of the optical tube, pulling air through the telescope and past the primary mirror. This helps the telescope to reach thermal equilibrium quickly. The fans are controlled by a computer if the optional Electronic Focus Accessory (EFA Kit) is purchased.  


Optical System

Optical Design Ritchey-Chrétien (RC)
Aperture 24 inch (610 mm)
Focal Length 6469 mm (254.68 inch)
Focal ratio F/10.6
Central Obstruction 30% of the Primary Mirror Diameter
Back Focus from Mounting Surface 10.3 inch (261.6 mm)
Back Focus from Racked in Focuser 7.3 inch (185.4 mm)
Weight 240 lbs (108.9 kg)
OTA Length 56 inch (1,422 mm)
Upper Cage Carbon Fiber Truss
Lower Cage Carbon Fiber Truss with Aluminum Light Shroud
OTA Width 31 inch (787 mm)
OTA Height 35 inch (889 mm)

Secondary Mirror

Diameter 6.89 inch (175 mm)
Material Fused Silica
Shape Hyperbolic
Coating Enhanced Aluminum – 96%

Primary Mirror

Optical Diameter 24 inch (610 mm)
Outer Diameter 24.5 inch (622 mm)
Shape Hyperbolic
Material Fused Silica
Coating Enhanced Aluminum – 96%


Crated Shipping Weight 500 lbs   (226.8 kg)
Crate Width 40 inch   (1,016 mm)
Crate Height 48 inch   (1,219 mm)
Crate Length 78 inch   (1,981 mm)

Included Items

CDK24 Focus Spacer (240343) This 5.3″ long spacer may be installed between the backplate and the focuser to take up some of the CDK24’s extra backfocus and reduce the torque placed on the focuser mechanism. This spacer is sized such that the backfocus distance behind the focuser will match that of the CDK20.
Primary Mirror Cover The Primary Mirror Cover protects the primary mirror.
Planewave thumb drive Includes instructions for Collimation and Spacing and software.
12VDC Power Supply Provides power for the fans (Not included for European Orders)
Wrench Set (5812A35) English Hex Wrenches (European Orders Only)

Personal Upgrade Path

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