|"When I consider your heavens, the work of your fingers, the moon and the stars which You have set in place, what is Man that You are mindful of him?" -- Psalm 8:3,4|
The core of my homemade autoguiding setup consists of GEM1 equatorial mount. Its hand controller was modified in order it was possible to control it by computer. The cradles delivered with my Europa scope have four holes with M4 threads on their top. I used that holes for attaching a homemade base plate construction which carries a guide scope. As a guide scope I used my second scope - 80mm F5 refractor.
Here there are some pictures which describe the whole setup. Click the images to see higher resolution photos. My SC modified webcam with Peltier cooling is attached to the main scope. The second webcam (non SC modified) is attached to guiding scope with 2X Barlow lens. Result focal length of guiding scope is 800mm. I could also use 3X Barlow lens, but the whole system is not stable enough, and then it is very difficult to find guiding star.
The system is controlled by computer. Two Philips webcams (Vesta 675SC2 and Vesta Pro 680) are connected to a single computer (look at trick, how to do it).
The webcams are handled by 2 running instances of K3CCDTools:
As I my measuring
results show, the system is quite stable and accurate
for guiding. The weakest point is fixation of the guiding
scope. It is hard to aim it to guiding star. The process
of aiming the main scope and guide scope is like
iteration (adjusting guide scope usually moves
photographed object from center FOV of main scope) and
must be repeated several times.
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Last Update: 07.10.2002