The PlaneWave Instruments CDK12.5 is a 12.5 inch (0.32 m) f/8 Corrected Dall-Kirkham Astrograph telescope. The telescope has a closed carbon fiber tube, with 3 cooling fans ejecting air from the back of the telescope. The CDK12.5 covers a 52 mm field of view without any field curvature, off-axis coma, or astigmatism. The instrument weight is 46 lbs and comes standard with the large capacity 2.75 inch Hedrick focuser.
The CDK (Corrected Dall-Kirkham) Optical Design is an innovative solution for unsurpassed astroimaging quality at an affordable price. The CDK telescope design provides excellent imaging with large format CCD cameras while remaining superb for visual use. The CDK design far exceeds the off-axis performance of most commercial telescope designs including the Ritchey-Chrétien design.
This no-compromise design is unique in making the optical alignment forgiving and collimation very easy. This guarantees the user the best possible performance from the telescope. The end result at the image plane of the CDK design is no off-axis coma, no off-axis astigmatism, perfectly flat field (no off-axis defocus). The CDK design will give you pinpoint stars from the center to the corner of the field of view.
| Aperture | 12.5 inch (318 mm) |
| Focal Length | 2541 mm (100.04 inch) |
| Focal ratio | f/8 |
| Central Obstruction | 42% of the Primary Mirror Diameter |
| Back Focus from Mounting Surface | 10.445 inch (265 mm) |
| Back Focus from Racked in Focuser | 7.2 inch (183 mm) |
| OTA Length | 31 inch (787 mm) |
| Optical Tube | Carbon Fiber |
| Dimensions | |
| Weight (includes manual-focuser and dovetail) | 46 lbs (20.9 kg) |
| Weight (includes electronic-focuser and dovetail) | 48.5 lbs (22.0 kg) |
| Diameter | 4.65 inch (118 mm) |
| Material | Precision Annealed Borosilicate or Fused Silica |
| Shape | Spherical |
| Coating | Enhanced Aluminum - 96% |
| Optical Diameter | 12.5 inch (318 mm) |
| Outer Diameter | 13 inch (330 mm) |
| Shape | Prolate Ellipsoid |
| Material | Precision Annealed Borosilicate or Fused Silica |
| Coating | Enhanced Aluminum - 96% |
LENS GROUP
| Diameter | 70 mm (2.76 inch) |
| Number of lenses | 2 |
| Coating | Broadband AR Coatings (less than .5% reflected from 400 to 700nm) |
STANDARD FEATURES
| 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 |
| 2.75 inch Hedrick Focuser | Heavy duty no-slip focuser. The focus tube runs on 5 bearings and is driven by a leadscrew so there is no chance of slipping. Focus may be automated through a computer using PlaneWave's EFA Kit add-on. The draw tube travel is 1.3 inch. |
| Cooling Fans | Three fans blow out of the optical tube pulling air though the telescope and by the primary mirror. This helps the telescope to reach thermal equilibrium quickly. The fans are controlled by a switch on the optical tube or can be conrolled by a computer if the optional Electronic Focus Accessory (EFA Kit) is purchased. |
INCLUDED ACCESSORIES
| 2.75" to 2" Adapter (125355) | Adapts the 2.75" inner diameter of the focuser to a standard 2" inner diameter. This adapter is necessary when setting the primary to secondary spacing. The 125399 Visual 2.75" to 2" adapter is an optional accessory that is designed to space a 2" diagonal for visual use. |
| Ronchi Spacer (200354) | This spacer is used for setting the primary to secondary spacing. It has an 1-1/4 inner diameter and may be used with 1-1/4 oculars for collimation. |
| Ronchi Ocular | This ocular is a Ronchi screen used for setting the primary to secondary spacing. |
| OTA Cover | The OTA cover is for closing the front of the tube to protect the primary mirror and the inside of the optical tube. |
| Printed Instructions | For Collimation and Spacing |
| 12VDC Power Supply (18778) | Provides power for the fans (Not included for European Orders) |
| Wrench Set (5812A35) | English Hex Wrenches (European Orders Only) |
| Type | Alt-Azimuth / Equatorial Direct Drive Mount |
| Weight | 110 lbs (50 kg) |
| Max. Load Capacity | 100 lbs (45 kg) |
| Latitude Range | 0 to 90 degrees, Northern and Southern hemispheres |
| Cable Management | Equipment cables can be wired through mount |
| Control Electronics | PlaneWave Interface dual axis telescope control |
| User Interface | PlaneWave Interface 4 (PWI4) Control Software with integrated PointXP mount modeling software |
| Homing Sensors | Home position sensors are included allowing the mount can find its home position on power up. |
| Slew Rate | 20 degrees per second (standard); 50 degrees per second (maximum), both axes |
| Power Requirement | Accepts 120 VAC. Supplied with 12VDC 15A Regulated Power Adapter |
| Motor Control | Industrial grade brushless motor control system and built in electronics |
| Motor - Azimuth and Altitude | Direct Drive 3 Phase Axial-Flux Torque Motors |
| Encoder - Azimuth and Altitude | 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 Torque | Approximately 20 ft-lbs continuous; 50 ft-lbs peak |
| Drive Electronics | Industrial grade, off-the-shelf brushless motor drives for each axis with custom designed interface card |
| Telescope Control Software | PlaneWave Interface (PWI4). Incorporates PointXP mount modeling software by Dave Rowe All ASCOM compatible. |
| Pointing Accuracy | <10 arcsecond RMS with PointXP Model |
| Pointing Precision | 2 arcsecond |
| Tracking Accuracy | < .3 arcsecond error over 5 minute period |
| System Natural Frequency | 10 Hz or greater |
For all orders exceeding a value of 100USD shipping is offered for free.
Returns will be accepted for up to 10 days of Customer’s receipt or tracking number on unworn items. You, as a Customer, are obliged to inform us via email before you return the item.
Otherwise, standard shipping charges apply. Check out our delivery Terms & Conditions for more details.
