PlaneWave CDK 24"
The CDK24 is a 24 inch (0.61 m) f/6.5 Corrected Dall-Kirkham Astrograph telescope. The CDK24 covers a 70 mm field of view without any field curvature, off-axis coma, or astigmatism. The instrument weight is 240 lbs (109 kg) and comes standard with a back plate retaining ring ready to accept the focuser of your choice.
The PlaneWave CDK 24 is available in various types of mirror material. Standard mirror material is borosilicate. The telescope is also available in fused silica optics, Ritchey-Chrétien (RC) optics and infrared optimized.
Fused Silicia is a synthetic amorphous silica glass of the highest purity and one of the most transparent glasses made. The optical and thermal properties of fused silica are superior to other types of glass due to its purity. Its transmission and homogeneity exceed those of crystalline quartz without the problems of temperature instability inherent in the crystalline form. Fused Silica has a coefficient of thermal expansion six times lower than Borosilicate (Pyrex) glass, which means that as fused silica cools down, it preserves its shape to a high degree of accuracy. This translates into consistent optical performance and unchanging focus over temperature changes. With its high melting temperature ()~ 1.600 degree Celsius), a very low coefficient of thermal expansion and resistance to thermal shock, fused silica is the material of choice for professional observatories as well as various scientific applications.
The abbreviation CDK stands for the optical system of the PlaneWave astrographs - a Dall Kirkham Cassegrain with a optical correction unit. The CDK design far exceeds the off-axis performance of most commercial telescope designs including the Ritchey-Chrétien design. More about the Optical Design (CDK).
New "state of the art" observatory at the University of Leicester
At the Advanced Imaging Conference (AIC) in Santa Clara, California in October 2010 AstroPhysics and Planewave exhibited togehter to showcase their 24" CDK (Corrected Dall-Kirkham) Astrograph on the Astro-Physics 3600GTO German Equatorial. The scope weighs 240 lbs and the counterweights are an additional 240 lbs.
Ray Gralak presented the beta version of a new software - Astrophysic Command Center - which allows to control all GTO mounts with GTOCP3 control box.
More pictures and videos are available here: www.astro-physics.com
The CDK 24 was "the audience magnet" at the 26th ATT in Essen
Europe premiere for the CDK 24" Dall Kirkham Astrograph telescope by PlaneWave Instruments, 610 mm aperture, f / 6.8 and 70 mm image field - absolutely free from coma and astigmatism.
Pictures taken by CDK24":
Aperture 24 inch (610 mm) Focal Length 3962 mm (155.98 inch) Focal ratio f/6.5 Central Obstruction 47% of the Primary Mirror Diameter Back Focus from Mounting Surface 14.1 inch (358 mm) Back Focus from Racked in Focuser 5.81 inch (148 mm) Weight 240 lbs (108.9 kg) OTA Length 56 inch (1,422 mm) UpperCage Carbon Fiber Truss Lower Cage Carbon Fiber Truss with Aluminum Light Shroud OTA Width 31 inch (787 mm) OTA Height 35 inch (889 mm) Optimal Field of View 70mm Image Circle
Diameter 9.45 inch (240 mm) Material Precision Annealed Borosilicate or Fused Silica Shape Spherical Coating Enhanced Aluminum - 96%
Optical Diameter 24 inch (610 mm) Outer Diameter 24.5 inch (622 mm) Shape Prolate Ellipsoid Material Precision Annealed Borosilicate or Fused Silica Coating Enhanced Aluminum - 96%
Diameter 135 mm (5.31 inch) Number of lenses 2 Coating Broadband AR Coatings (less than .5% reflected from 400 to 700nm)
Carbon Fiber Tube Design Minimizes thermal expansion which causes focus shift with changes in temperature Dovetail expansion joint Allows 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 Fans Three cooling fans blow air inside the back of the telescope. 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. Delta-T Ready For added dew prevention, the CDK14 is internally wired with polyimide film heater pads and temperature sensor, ready to be controlled with the optional Delta-T controller.
|Optical Design||Corrected Dall-Kirkham (CDK)|
|Back Focus Distance||14.1" (358 mm) from Mounting Surface, 5.81" (148 mm) from Racked in Focuser|
|Aperture (mm)||24" (610 mm)|
|Focal Length||3.962 mm (155.98 inch)|
|Image Field||70 mm|
|Central Obstruction||47% of the Primary Mirror Diameter|
|Optical tube length||55,98 inch (1.422 mm)|
|Optical Tube Weight Copy||240 lbs (109 kg)|