CCD camera Atik 460EX attached to the big refractor

I bought recently a 140mm apochromatic refractor with 980mm focal length made by TEC to image larger areas than I could do with the C9. The refractor has an oil spaced triplet front lens that eliminates the colour aberration completely. The telescopes made by TEC belong to the premium class of refractors for amateurs regarding optical and mechanical quality. TEC developed recently its own focuser that replaces the focuser from Starlight Instruments that was mounted before. The focuser is extremly solid and I could not identify any flaws or shortcomings. The focuser has a dual speed transmission for adjusting the focus precisely. This precision is absolutely necessary to get sharp images. Turning the focusing knob for a small angle is sufficient to be out of focus. Also, when the temperature drops for more than 1°C re-focusing is necessary.

For visual observing a 2" star diagonal is needed because the 100mm travel length of the focuser is too short to reach focus. For imaging extension tubes are necessary, too. The focuser comes with a 2" adapter that clamps eyepieces and accessories concentrically. This way I mounted the 2" flattener from TS.

The second and mainly used option is the 0.75x reducer and flattener designed by Riccardi. With the reducer and the Atik 460EX CCD camera the field of view is 60 x 45 arcminutes. The correction is perfect even in the corners and delivers sharp tiny stars. The illumination of the 16mm diameter CCD sensor is virtually 100%. A slight vignetting can be observed when the contrast is very much boosted. But that can be handled easily with artificial flats.

The refractor is mounted on a large 3" dove tail plate using TEC's quick mount tube rings. It can be quickly replaced by the C9 which has the same weight. Therefore re-balancing is not necessary when exchanging these two telescopes. When imaging through the refractor with the Atik 460EX CCD camera the setup is guided by the Watec 120N CCTV camera at the parallel mounted 90mm refractor using TVGuider.

  1   Tube of 140mm TEC refractor
  2   3.5"-focuser made by TEC
  3   Adapter M63 for attaching the Riccardi reducers
  4   M63 Riccardi reducer (0,75X) and flattener
  5   Adapter from M63 to T2 and Baader T2 micro dove tail changer system
  6   Brightstar USB-filter wheel "Quantum" for 7 1,25" filters
  7   Atik 460EX monochrome, cooled CCD camera with 6 megapixels
  8   USB cable to CCD camera
  9   12V power supply of camera
10   2,5" focuser of 90mm APO
11   2" extension tube to reach focus with Watec CCTV camera
12   Watec 120N CCTV camera with high sensitivity
13   Cable to control module 15
14   combined video and power supply cable from TVGuider
15   Control module for Watec 120N CCTV camera
16   USB cabel for control and power supply of motorised filter wheel
17   Finder scope to facilitate centering of bright stars on the CCD camera when re-calibrating the Gemini GoTo system