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CDK17 Optical Tube Assembly

SKU# 170101Q

Price: $22,500.00


The CDK17 is an innovative telescope for unsurpassed astroimaging, research, or satellite tracking.

  • f/6.8 and 2939mm focal length.
  • No coma, no off-axis astigmatism, and no field curvature.
  • Pinpoint stars across a 70mm image circle.
  • Rock solid fused silica mirrors with low thermal expansion.
  • Carbon fiber optical tube assembly for rigidity and fast cooling.
  • Simple secondary mirror collimation thanks to the fixed primary mirror.


Capturing the most stunning astrophotographs possible is something our team is passionate about. From design to manufacture, our goal with the Corrected Dall-Kirkham (CDK) 17″ telescope was centered around performance and ease of use. The CDK17 is an incredible breakthrough in telescope technology and produces no off-axis coma and no off-axis astigmatism. Additionally, the CDK17 provides a perfectly flat field so your astrophotographs will have stunning clarity from corner to corner of the image without field curvature degrading the photos. Offering the simplicity of single-mirror collimation, the stray light control of advanced baffles, structural performance created through finite element analysis (FEA), and decades of telescope design experience, the CDK17 is an exceptional diffraction-limited telescope. CDK17 users can experience pinpoint stars edge-to-edge and a 61 x 61 arcminute field of view when using large 16803 size camera sensors. When equipment fades into the background and simply performs, the astrophotography experience becomes even more fun and rewarding!

Checkout more about our technology and optical design here.


CDK 17 Features

Carbon Fiber Truss Design


Minimizes thermal expansion which causes focus shift as temperature changes during an imaging session. Carbon fiber also reaches ambient temperatures quickly and is extremely lightweight and rigid to help ensure excellent imaging data is produced.

3D Printed Baffles


PlaneWave uses digital 3D printing technology to produce lightweight baffle tubes. 3D printers add successive layers of material to construct a baffle system with precision positioned internal stray light baffles to minimize vignetting and maximize image contrast. Quality baffling makes an incredible difference in overall image quality, so we ensured an optimal design was created for our telescopes.

Dovetail Expansion Joint


Allows for 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. This results in images that are not distorted due to expansion, or contraction of the optical tube materials.

Delta-T Ready


For added dew prevention, the CDK17 is internally wired with polyimide film heater pads and temperature sensor, which is ready to be controlled with the Delta-T via PlaneWave Interface 3 software.

Cooling Fans


Three fans on the backplate of the optical tube pull air through the telescope and by the primary mirror. Three fans on the side of the optical tube also blow air across the primary to ensure a boundary layer of air does not distort images. These fans help the telescope reach thermal equilibrium quickly, further reducing any distortion in images due to temperature variations. The fans are controlled by a switch on the optical tube, or can be controlled by via PWI3 software if a PlaneWave Electronic Focus Accessory (EFA Kit) is purchased.



Optical System

Optical DesignCorrected Dall-Kirkham
Aperture17 inch (432 mm)
Focal Length2939 mm (115.71 inch)
Focal ratioF/6.8
Central Obstruction23.7% by surface area; 48.6% of the primary mirror diameter
Back Focus from Mounting Surface10.32 inch (262.33 mm)
Back Focus from Racked in Focuser7.24 inch (184 mm)
Weight106 lbs (48 kg)
OTA Length42 inch (1067 mm)
Optical Performance6.5 micron rms at 21mm and 9.6 micron at 26mm off-axis
Upper CageCarbon fiber truss
Lower CageCarbon fiber truss with carbon fiber light shroud
Optimal Field of View70mm image circle

Secondary Mirror

Diameter190 mm (7.48 inch)
MaterialFused silica (quartz)
CoatingEnhanced aluminum – 96%

Primary Mirror

Optical Diameter17 inch (432 mm)
Outer Diameter17.5 inch (445 mm)
ShapeProlate ellipsoid
MaterialFused silica (quartz)
CoatingEnhanced aluminum – 96%

Lens Group

Diameter105 mm (4.13 inch)
Number of lenses2
CoatingBroadband AR Coatings (less than .5% reflected from 400 to 700nm)

Standard Features

Carbon Fiber Truss DesignMinimizes thermal expansion which causes focus shift with changes in temperature
Dovetail Expansion JointAllows for the difference in thermal expansion between carbon fiber and aluminum. The expansion joint allows the aluminum dovetail expand and contract without stressing the carbon fiber lower truss
Cooling FansThree cooling fans ejecting air from the back of the telescope and four fans blowing across the boundary layer of the mirror surface. 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.


Crated Shipping Weight225 lbs   (102.1 kg)
Crate Width30 inch   (762 mm)
Crate Height37 inch   (940 mm)
Crate Length58 inch   (1,473 mm)

Included Accessories

Primary Mirror CoverTo protect the primary mirror
PlaneWave Thumb DriveContains software and instructions for collimation and spacing the primary to secondary mirror
12VDC Power SupplyProvides power for the fans (Not included for European orders)
Wrench Set
Standard hex wrenches (European orders only)

Included Items

Included Items

Included Items

Heating elements for dew preventionThe heating pads on the primary and secondary mirror require the 600195 Delta-T controller sold separately
OTA CoverTo protect the primary mirror and inside of the optical tube
FlashdriveContains software and instructions for collimation and spacing the primary to secondary mirror
Wrench Set (5812A35)Standard hex wrenches (European orders only)



For warranty information please check our Standard Warranty Page.