Astrotracker Mk 2
I had earlier put up my simple device for astrophotography which was essentially a miniature equatorial made using bicycle hub driven by a tangent arm. This I called ”Astrotracker”. This used a drive arrangement with a string pulling the drive arm. Although this worked Ok it was not very satisfactory as the string did not allow precise enough motion. So I have modified it. Now the arm is driven by a screw and instead of a wooden strip the Tangent arm is made of a long rod with threads on one end and is bent round on the other which goes around axle.
I have taken photos turning the drive manually at a quarter rotation every 15 secs for an exposure of five minutes. The pics show nice images without trailing.
The Astrotracker Mark 2 is shown below
The Camera is mounted such that the film centre is on the RA axis
(Please click on pictures to see larger version)
The Astrotracker Mk 2 shown without the Camera
Detail views
The Astrotracker Mk 2 being used a simple Heliostat during Venus Transit
