PlaneWave CDK20 Telescope (f/7.77)

Starting Price: $39,000.00
Price as Configured: $39,000.00
Brand: PlaneWave Instruments / SKU: PW-200127Q
The CDK20 f/7.77 from PlaneWave Instruments stands as a pinnacle of engineering excellence, tailored for serious astrophotographers and astronomers who demand precision and performance. With its advanced technology and high-quality design, the CDK20 f/7.77 delivers outstanding images for a wide range of advanced observational and scientific applications.

The CDK20 f/7.77 is characterized by its exceptional specifications and features:
  • 20-inch (508 mm) aperture
  • 3951 mm focal length
  • f/7.77 focal ratio
  • 269.49 mm back focus from mounting surface
  • Perfectly flat field across the entire 52mm image circle
  • No off-axis coma or astigmatism
  • Rock-solid fused silica mirrors with low thermal expansion
  • Lightweight and rigid carbon fiber optical tube assembly
NOTE: Shipping cost will be determined after the order is made and must be paid for before the mount will ship. A shipping quote can be obtained on request.
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PW-200150 - PlaneWave Counterweight Accessory for CDK14 & 20
PW-200150 - PlaneWave Counterweight Accessory for CDK14 & 20
$265.00
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PW-200150 - PlaneWave Counterweight Accessory for CDK14 & 20
About This Product
Counterweights and Bracket for CDK14 (Front Ring Only) and CDK20, comes with three 0.5 LB Stackable (#125382) weights.
PW-200166 - PlaneWave Reducer 0.66X CDK20/24
PW-200166 - PlaneWave Reducer 0.66X CDK20/24
$1,600.00
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PW-200166 - PlaneWave Reducer 0.66X CDK20/24
About This Product

This is a reducer designed specifically for flat field telescopes like the CDK. This reduces the f ratio of the CDK telescope 66%. The f/6.8  CDK20 telescopes will be reduced to about f/4.5.

**NOTE – 200166 adapter is also compatible with CDK17 that have 8.81″ back focus.   CDK17 with 10.24″ back focus will use the 125166 focal reducer. See instruction manual for details.

PW-2002101 - PlaneWave Sliding Counterweight System Rail & Brackets for CDK20
PW-2002101 - PlaneWave Sliding Counterweight System Rail & Brackets for CDK20
$690.00
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PW-2002101 - PlaneWave Sliding Counterweight System Rail & Brackets for CDK20
About This Product
Requires sliding weight system counterweights, not included.
PW-2002010 - PlaneWave CDK20 F/7.77 Corrector Lens Assembly
PW-2002010 - PlaneWave CDK20 F/7.77 Corrector Lens Assembly
$1,600.00
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PW-2002010 - PlaneWave CDK20 F/7.77 Corrector Lens Assembly
About This Product

This is lens group is designed to convert a CDK20 f/6.8 to f/7.77. The original lens group is unscrewed from the backplate of the optical tube and replaced with the new lens group.

  • Adds 1.9″ of backfocus to the optical tube for those requiring additional imaging train components.
  • Increases focal to 3951mm, which is an additional 497 mm of focal compared to the standard CDK20 f/6.8.
PW-2003136 - PlaneWave Solid Aluminum Shroud CDK20 (Factory Installation Required)
PW-2003136 - PlaneWave Solid Aluminum Shroud CDK20 (Factory Installation Required)
$920.00
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PW-2003136 - PlaneWave Solid Aluminum Shroud CDK20 (Factory Installation Required)
About This Product
Enhance the protection of your telescope’s primary mirror with our Solid Aluminum Shrouds.

Specifically designed for OTAs like the CDK14, CDK17, CDK20, and CDK24, these ruggedized shrouds offer debris and light mitigation ensuring optimal optical performance.
PW-200398 - PlaneWave Counterweight Bracket for CDK14 (Front-Ring Only) & 20
PW-200398 - PlaneWave Counterweight Bracket for CDK14 (Front-Ring Only) & 20
$80.00
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PW-200398 - PlaneWave Counterweight Bracket for CDK14 (Front-Ring Only) & 20
About This Product
Bracket, Counterweight for CDK14 (Front Ring Only) and CDK20
PW-200399 - PlaneWave Visual Adapter - CDK20/24
PW-200399 - PlaneWave Visual Adapter - CDK20/24
$184.00
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PW-200399 - PlaneWave Visual Adapter - CDK20/24
About This Product
This 3.5″-2″ Visual Adapter, for the CDK20 and CDK24, slides into the optional 3.5″ Hedrick Focuser. The adapter steps the 3.5″ opening down to 2″ for standard 2″ accessories. The adapter also adds some additional spacing to optimize the use of a 2″ diagonal so focus is reached with most eyepieces.
PW-200915 - PlaneWave Ronchi Eyepiece and Adapter Kit for CDK20/CDK24
PW-200915 - PlaneWave Ronchi Eyepiece and Adapter Kit for CDK20/CDK24
$460.00
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PW-200915 - PlaneWave Ronchi Eyepiece and Adapter Kit for CDK20/CDK24
About This Product
The Ronchi Eyepiece and Adapter Kit is available for CDK 12.5, CDK 14, CDK 17, CDK 20, and CDK 24. This adapter kit includes 3 pieces: an adapter for the Hedrick Focuser, a Ronchi Eyepiece, and a Ronchi Eyepiece Spacer.
PW-200970 - PlaneWave CDK20 Fabric Light Shroud
PW-200970 - PlaneWave CDK20 Fabric Light Shroud
$207.00
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PW-200970 - PlaneWave CDK20 Fabric Light Shroud
About This Product
This is a spandex fabric light shroud that blocks out stray light and minimizes dust on the primary mirror.
PW-600166 - PlaneWave Reducer, Lens .66x for IRF90 & CDK20/24
PW-600166 - PlaneWave Reducer, Lens .66x for IRF90 & CDK20/24
$1,600.00
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PW-600166 - PlaneWave Reducer, Lens .66x for IRF90 & CDK20/24
About This Product
The PlaneWave 0.66x Reducer is engineered specifically for flat-field telescopes like the CDK20 or CDK24, optimizing focal length for enhanced imaging capabilities. This model, designed for use with the IRF90 rotating focuser, features a low-profile build to accommodate cameras that require extra back focus. While the reducer itself has minimal back focus, it does utilize a substantial portion of the telescope’s overall back focus, so precise spacing is essential. When paired with a compatible camera, this reducer decreases the CDK’s focal ratio while maintaining top-tier optical performance.
PW-600332 - PlaneWave Adapter, CDK20 to AP Female
PW-600332 - PlaneWave Adapter, CDK20 to AP Female
$207.00
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PW-600332 - PlaneWave Adapter, CDK20 to AP Female
About This Product
This adapter mounts in place of a focuser on CDK14/17/20 & 24 models and has the standard AP female threads.
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Price as Configured: $39,000.00

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Large Aperture and Moderate Focal Ratio
The CDK20 f/7.77 features a 508 mm aperture and a high f/7.77 focal ratio. This configuration provides excellent light-gathering efficiency and image scale, making it ideal for detailed lunar, planetary, and deep-sky imaging.

Advanced Optical Design
The CDK20 f/7.77 has a state-of-the-art Corrected Dall-Kirkham optical system that offers exceptional image clarity. This design eliminates off-axis coma and astigmatism and delivers a perfectly flat field, ensuring that images are crisp and detailed across the entire field of view with minimal post-processing required.

Robust Mechanical Structure
Constructed with a carbon fiber optical tube, the CDK20 f/7.77 is lightweight and sturdy. Its thermal expansion coefficient ensures minimal focus shift with temperature changes, making it suitable for extended observing sessions under diverse environmental conditions.

High-Performance Mirrors and Coatings
Featuring fused silica mirrors, the CDK20 f/7.77 maintains precise optical alignment and surface accuracy, even with temperature fluctuations. Its high-quality coatings maximize light transmission and minimize stray light, optimizing performance for critical observational tasks.

Thermal Management
The CDK20 f/7.77 includes cooling fans and a Delta-T ready system to achieve thermal equilibrium rapidly. These features reduce air turbulence within the tube, minimizing image distortion and maintaining consistent imaging quality.

Integrated Dew Control
The telescope incorporates advanced dew prevention technology with heater pads controlled by PlaneWave’s software. This ensures optical surfaces remain clear of condensation in humid conditions, maintaining clear and consistent imaging performance.

Application-Specific Benefits
Astrophotography
With its precise focal ratio and large image circle, the CDK20 f/7.77 allows astrophotographers to capture detailed and expansive views of the cosmos, providing incredible detail and clarity.

Astronomy Research
The stable and precise imaging capabilities of the CDK20 f/7.77 make it an invaluable tool for academic institutions and observatories engaged in sophisticated astronomical research, including detailed photometric studies and complex deep-sky surveys.

Visual Observations
The CDK20 f/7.77 excels in visual observation, offering bright and crisp views ideal for star parties and serious visual astronomy. The telescope's significant aperture and excellent optical quality provide stunning views of planetary, lunar, and deep-sky objects, making every viewing session a memorable experience.

Space Situational Awareness (SSA) and Space Domain Awareness (SDA)
The CDK20 also lends itself to Space Situational Awareness and Space Domain Awareness applications. Its capability to provide detailed observations can be essential for tracking and monitoring satellites and other space debris, contributing valuable data for space traffic management and safety initiatives.