PlaneWave CDK400 Telescope System f/6.8
Based on the technology of our PW-1000 (1-meter) Observatory telescope, PlaneWave combines its revolutionary optical systems with its brand new innovative L-Series direct drive mount that sets a new standard for small observatory telescopes.
The PlaneWave Instruments CDK17 is a 17 inch (0.43 m) f/6.8 Corrected Dall-Kirkham Astrograph telescope. The CDK17 covers a 70 mm field of view without any field curvature, off-axis coma, or astigmatism. The instrument weight is 94 lbs (43 kg) and comes standard with a back plate retaining ring ready to accept the focuser of your choice.
The abbreviation CDK stands for the optical system of the PlaneWave astrographs - a Dall Kirkham Cassegrain with a optical correction unit. More about the Optical Design (CDK).
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.
Images taken with CDK17":
The L-Series combines versatility, simplicity and affordability by combining all the technology of our Observatory class telescopes into a compact stand-alone mount.
The mount is equipped with direct drives motors as well as high-resolution encorders. The software is ASCOM compatible and the direct drive motors can move the telescope at incredible speeds for tracking satellites.
In its Alt/Az configuration it is considerably more compact than its equatorial counterpart, allowing a larger telescope to fit in a smaller enclosure. The mass it takes to make a rigid alt/az mount is substantially less, leading to cost savings. Unlike German Equatorial mounts, there are no meridian flips to deal with, and no large protruding counterweights to create a dangerous hazard in a public observatory. Alt/Az is more intuitive to use and no polar alignment is needed.
- Direct-drive motors on each axis for smooth, fast, and virtually silent movement of the telescope
- Slew speeds up to 50 degrees per second
- High resolution encoders on each axis for precise positioning
- Zero backlash, Zero periodic error
- Latitude Range: 0 to 90 degrees, Northern and Southern hemispheres
- Enclosed electronics
- Through the mount cabling: Access panels in the fork arm and azimuth axis allow for camera equipment cabling through the inside of the mount.
- Dual mounting bracket: PlaneWave style mounting bracket to hold CDK17/20 onto inside of fork arm with additional option of mounting a scope on the outside of the fork arm. Optional dovetail clamp required.
- Azimuth dovetail balance system: For precise center of gravity balance whether in Alt-Az or Equatorial configuration
- User Interface: PlaneWave Interface 4 (PWI4) Control Software with integrated PointXP mount modeling software
- Slew Rate: 20 degrees per second (standard); 50 degrees per second (maximum), both axes
- Home position sensors are included allowing the mount can find its home position on power up.
|Optical Design||Corrected Dall-Kirkham (CDK)|
|Aperture (mm)||17" (432 mm)|
|Focal Length||2.939 mm (115.71 inch)|
|Image Field||70 mm|
|Back Focus Distance||10.24" (260 mm) from Mounting Surface, 7.24" (184 mm) from Racked in Focuser|
|Central Obstruction||23.7 % by surface area, 49% of the Primary Mirror Diameter|
|Optical Tube Weight||106 lbs (48 kg)|
|Mount||Equatorial & Alt-Az Single-Arm mount|
|Payload Capacity (kg)||200 lbs (91 kg)|
|Mount Type||Alt-Az or Equatorial configuration|
|Mount Weight||100 kg|
|Latitude Range||0 to 90 degrees, Northern and Southern hemisphere|
|Slew Speeds||20 degrees per second (standard); 50 degrees per second (maximum), both axes|
|Tracking Accuracy||< .3 arcsecond error over 5 minute period|
|All-sky pointing accuracy||<10 arcsecond RMS with PointXP Model|
|Pointing Precision||2 arcsecond|
|System Natural Frequency||10 Hz or greater|
|Software||PlaneWave Interface (PWI4). Incorporates PointXP mount modeling software by Dave Rowe All ASCOM compatible|
|Homing Sensors||Home position sensors are included allowing the mount can find its home position on power up|
|Motor Torque||Approximately 20 ft-lbs continuous; 50 ft-lbs peak|
|Motor||Azimuth and Altitude: Direct Drive 3 Phase Axial-Flux Torque Motors|
|Control system electronics||PlaneWave Interface dual axis telescope control|
|Encoder||152mm disk built into the azimuth and altitude axes with stainless steel encoder on the circumference with reader yields 18,880,000 counts per revolution of the telescope. This translates to about 0.069 arcsecond resolution|
|Motor Control||Industrial grade brushless motor control system and built in electronics|
|Power Requirements||Accepts 120 VAC. Supplied with 12VDC 15A Regulated Power Adapter|