Dane techniczne:
- System teleskopowy: Tylko tuba optyczna (OTA)
- Rodzaj teleskopu: Dall-Kirkham (Optimised), Astrograph
- Seria teleskopów: CDK
- Marka teleskopu: PlaneWave instruments
- Przysłona teleskopu (zasięg): 300mm - 499mm
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 52mm 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. (no Efa Kit)
The new CDK optical design is the innovative solution for unsurpassed astroimaging quality at an affordable price. The purpose of the design is to provide a telescope that will excel at 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. The RMS spot sizes at the edge of a 52mm diameter image circle yield are 12 microns, about the size of a pixel of most CCD cameras.
This no-compromise design is unique in making the optical alignment very forgiving and collimation very easy. This guarantees the user will be sure to get the best performance out of the telescope possible. 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), all the way out to a 52mm image circle. All this means, the stars will be pinpoints from the center of the field of view out to the corner of the field of view.
The new CDK optical design is the innovative solution for unsurpassed astroimaging quality at an affordable price. The purpose of the design is to provide a telescope that will excel at 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. The RMS spot sizes at the edge of a 52mm diameter image circle yield are 12 microns, about the size of a pixel of most CCD cameras.
This no-compromise design is unique in making the optical alignment very forgiving and collimation very easy. This guarantees the user will be sure to get the best performance out of the telescope possible. 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), all the way out to a 52mm image circle. All this means, the stars will be pinpoints from the center of the field of view out to the corner of the field of view.
The new CDK optical design is the innovative solution for unsurpassed astroimaging quality at an affordable price. The purpose of the design is to provide a telescope that will excel at 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. The RMS spot sizes at the edge of a 52mm diameter image circle yield are 12 microns, about the size of a pixel of most CCD cameras.
This no-compromise design is unique in making the optical alignment very forgiving and collimation very easy. This guarantees the user will be sure to get the best performance out of the telescope possible. 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), all the way out to a 52mm image circle. All this means, the stars will be pinpoints from the center of the field of view out to the corner of the field of view.
The new CDK optical design is the innovative solution for unsurpassed astroimaging quality at an affordable price. The purpose of the design is to provide a telescope that will excel at 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. The RMS spot sizes at the edge of a 52mm diameter image circle yield are 12 microns, about the size of a pixel of most CCD cameras.
This no-compromise design is unique in making the optical alignment very forgiving and collimation very easy. This guarantees the user will be sure to get the best performance out of the telescope possible. 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), all the way out to a 52mm image circle. All this means, the stars will be pinpoints from the center of the field of view out to the corner of the field of view.
Specification:
Aperture | 12.5" |
Focal Length | 2541 mm |
Focal ratio | f/8 |
Central Obstruction | 41% |
Back Focus | 10.445" from focuser mounting surface, 7.2" from racked in focuser |
Weight | 46 lbs |
OTA Length | 31" |
Optical Tube | Carbon Fiber |
Optical Performance | Spot and Vignetting Plot - Spot and Diffraction Diagrams |
Overall Dimensions | Dimensions PDF |
Primary Mirror
Diameter | 13" |
Aperture | 12.5" |
Focal ratio | f/3 |
Mounting | Laser Collimated and Permanentely Fixed |
Material | Precision Annealed Pyrex |
Shape | Prolate Ellipsoid |
Coating | Enhanced Aluminum - 96% |
Secondary Mirror
Diameter | 4.65" |
Material | Precision Annealed Pyrex |
Shape | Spherical |
Coating | Enhanced Aluminum - 96% |
Lens Group
Diameter | 70mm |
Number of lenses | 2 |
Coating | Broadband AR Coatings (less than .5% 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 |
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. |
SHIPPING
Crated Shipping Weight | 163 lbs (73.9 kg) |
Crate Width | 22 inch (559 mm) |
Crate Height | 29 inch (737 mm) |
Crate Length | 48 inch (1,219 mm) |
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) |
- System teleskopowy
- Tylko tuba optyczna (OTA)
- Rodzaj teleskopu
- Astrograph*~Dall-Kirkham (Optimised)
- Seria teleskopów
- CDK
- Przysłona teleskopu (mm)
- 320mm*~
- Ogniskowa teleskopu (mm)
- 2541mm
- Telocalope Focal Ratio (F)
- F8