Cassegrain Telescopes

CDK & RC Cassegrain

The Hubble Corrected Dall-Kirkham (CDK) is a revolutionary optical design offering a large, flat focal surface perfect for modern high-resolution CCD cameras. Featuring our sandwich mirror technology for rapid thermal equilibrium and a completely CNC-machined closed tube OTA optimized for zero thermal focal shift, the CDK delivers affordable, high-performance astrophotography and visual use.

Starts at $4,999 USD

CDK telescope optical testing CDK telescope testing setup Hubble CDK Corrected Dall-Kirkham telescope CDK telescope OTA assembly

CDK17 at Irydeo Observatory

CDK17 at Irydeo Observatory CDK17 first light test after collimation CDK17 with Takahashi reducer at f/5 CDK17 NEO observation at Irydeo Observatory CDK17 NEO tracking data from Irydeo Observatory

"It is a raw image, with nothing special... except the focal length... ~2200mm!! Yes, it is working at ~ f/5; after some tests, I attached a second-hand Takahashi CR 0.73x reducer... and it works! The field is almost flat (I need to improve the collimation a bit more, and it will be 100% flat). Its performance is amazing, together with a 22.5mm x 22.5mm sensor (QHY42 sCMOS)."

— Francisco José Calvo, Irydeo Observatory

"It continues working hard... Tonight, we reported two new potential NEOs, one of which has a MOID of only 0.005 AUs:"

— Francisco José Calvo, Irydeo Observatory

Revolutionary Optical Design

The Corrected Dall-Kirkham (CDK) optical configuration provides a large, flat focal surface that is perfect for modern, high-resolution CCD cameras. An affordable, high-performance solution for astrophotography and visual use.

Outstanding Image Quality

Premium quality, diffraction-limited optical systems deliver stunning views of the heavens. Combined with our revolutionary sandwich primary, CDK optics bring superior optical performance in real-world situations.

Sandwich Mirror Technology

Our mirrors reach thermal equilibrium extremely fast without active cooling. Active cooling systems such as fans introduce micro-vibration that degrades image quality — our sandwich mirrors eliminate this problem entirely.

CNC-Machined OTA

Our 2-section completely CNC-machined closed tube OTA is optimized for zero thermal focal shift and is structurally much stronger than a single section tube. Built for precision and durability.

Optical Aperture 254mm
System Focal Ratio 8
Focal Length 2032mm
Field Of View 55mm
Obstruction Ratio 40%
Back Focus 110mm
Focuser 3" Dual Speed Crayford
Weight 14.5 kg (32 lbs)
OTA Length 622mm
Coating 96% enhanced
Delivery ~30 Days
CDK10 spot diagram CDK10 f/8 OTA front view CDK10 f/8 OTA side view CDK10 f/8 OTA rear view
Optical Aperture 317.5mm
System Focal Ratio 8
Field Of View 60mm
Obstruction Ratio 40%
Back Focus 163.5mm
Focuser 3" dual speed Crayford
Weight 22.7 kg (50 lbs)
OTA Length 762mm
Coating 96% enhanced
Delivery ~60 Days
CDK12.5 spot diagram CDK12.5 f/8 OTA front view CDK12.5 f/8 OTA side view CDK12.5 f/8 OTA rear view
Optical Aperture 432mm
System Focal Ratio 6.8
Field Of View 70mm
Obstruction Ratio 40%
Back Focus 228mm
Focuser 3" dual speed Crayford
Weight 42 kg (93 lbs)
OTA Length 950mm
Coating 96% enhanced
Delivery ~90 Days
CDK17 spot diagram CDK17 f/6.8 OTA front view CDK17 f/6.8 OTA side view CDK17 f/6.8 OTA rear view
System Focal Ratio 6.8
Field Of View 70mm
Obstruction Ratio 40%
Back Focus 254mm
Focuser 3.5" dual speed Crayford
Weight 63.5 kg (140 lbs)
OTA Length 1052mm
Coating 96% enhanced
Delivery ~90 Days
CDK20 spot diagram CDK20 f/6.8 OTA front view CDK20 f/6.8 OTA side view CDK20 f/6.8 OTA rear view

To buy CDK Optics (Primary, Secondary Mirrors and Corrector) and also find out shipping costs, please e-mail us!

CDK10 f/8 $4,999
CDK12.5 f/8 $7,999
CDK17 f/6.8 $15,999
CDK20 f/6.8, f/11 $25,999
CDK24 f/6.5 $49,999
CDK700mm f/6.5 $77,999
CDK800mm f/6.5 $109,999
CDK40 f/6.5 Contact Us