Planewave CDK12.5 astrograph tube with 3' dovetail 1323212

The new CDK optical design, developed by PLANEWAVE INSTRUMENTS, is the most innovative solution currently available on the market for unparalleled quality in astrophotography at a reasonable price. The objective of the CDK design is to offer a telescope that excels in astrophotography with large format CCD cameras (SBIG STL type) and at the same time has a splendid performance in visual observation. The CDK (Dall-Kirkham field corrector) design far exceeds the performance of most commercial optical designs, including the famous Ritchey-Chrétien, in imaging the peripheral areas of the field of view. The RMS spot sizes in the peripheral zone of a 52mm diameter circular field of view are about 12 microns, i.e., about the size of a pixel in most current CCD cameras. This design is unique in making optical alignment an unobtrusive task and collimation an extremely easy operation. This ensures that the user can always get the best possible performance from his equipment. The end result in the focal plane of the CDK design is an image with no coma or astigmatism, neither in the central nor in the peripheral part of the field of view, and a perfect flat field (no field curvature). All this is achieved in a 52mm circular image. Therefore, the stars will be totally point-like objects from the center to the far corner of the field of view. System: Diameter: 12.5" (318mm) Focal Length: 2.541mm Focal Ratio: f/8 Central Obstruction: 39% Weight: 20.70kg Tube Length: 79cm Tube: closed carbon fiber Primary Mirror: Diameter: 330mm Aperture: 318mm Focal Ratio: f/8 Laser collimated and permanently fixed Material: Precision tempered Pyrex Geometry: Ellipsoidal Aluminum treatment enhanced with 96% reflection Secondary Mirror: Diameter: 118mm Material: Precision tempered Pyrex. Geometry: Spherical Aluminum treatment improved with 96% reflection Lens Group: Diameter: 70mm Number of Elements: 2 Broadband Treatment: anti-reflection treatment (less than 0.5% between 400 and 700nm) Standard Specifications : - Carbon fiber tube minimizes thermal expansion that produces focus variations due to temperature changes. - The expansion joint present in the dovetail compensates for the thermal expansion differences between carbon fiber and aluminum. The expansion joint allows the aluminum dovetail to expand and contract without stressing the carbon fiber structure. - 2.75" "Hedrick Heavy Duty" focuser. The focuser tube slides on 5 bearings and is moved by a screw mechanism so there is no possibility of focuser slippage. Accepts as optional items a Dial Indicator and EFA Kit (Electronic Focus Accessory) to control various electronic accessories. - Cooling fans: 3 fans blow filtered air over the rear of the primary mirror to help it achieve thermal equilibrium very quickly. The fans are controlled by a switch located on the optical tube or can be controlled from the PC if the optional EFA kit is purchased. Dimensions and Weight of the packing box : Dimensions: 104 X 58 X 79cm Weight: 73,9 Kg