Sunday, September 4, 2016

Pier collision on zenith imaging

On my first night at Likely Place, I wanted to image IC1318 - which happened to be almost exactly in the zenith at a certain time. I suddenly noticed some crazy guide star movement in PHD2 that could not be corrected. In fact, they got worse and worse. I first though that it had something to do with the backlash issues that I have. But then, the scope did a meridian flip and everything was back to normal.

The next day, I thought to check if the scope maybe hit the pier and couldn't move - and yes, it seems as if there was the chance that the filter wheel hit the control box:


I tried a few things:
  • Moving the control box lower? Didn't work as the guiding cables aren't long enough.
  • Moving the control box to the front (the scope is never anywhere near the front of the pier - but same as before, the RA guiding cable isn't long enough
  • Rotating the pier such that the box is exactly in the back (and thus destroying my polar alignment). Yes, that seemed to work.

Last night, no collisions - yei!

Though it does seem weird that I have to do this exact setup and that I never experienced that before (I'm sure I didn't always have the control box exactly in the back)...