|
A couple of questions on Losmandy Drives
I seem to be having a bit of a Losmandy Hoodoo atm when it comes to drives and backlash. What would be causing rubberbanding in the RA drive, particularly RA-, and a unusual backlash in Dec.
The rubber banding is quite pronounced through a C14 viewed via a ToUcam. Approx half the FOV. Could this be caused by RA worm too tight. I'd only just loosened the worm by 2 toi shortly before, but I may not have loosened enough.
In the backlash issue the Dec starts almost immediately when a key is pressed. But when the opposite key is pressed, the star starts to move immediately in the opposite direction, but then stops for a number of sec and then starts again. I have this problem on both my own mount and the Mapleton Observatory mount. I recently serviced my mount and reset the worm mesh, the Observatory one was done professionally. Both have the same issue.
On mine if I tighten the worm mesh up by more than 1 toi, the Gemini sends a Dec Motor Lag message, meaning the worm is too tight. So I can't go any tighter. Loosening seems to make the matter worse by lengthening the backlash period. It is currently about 12 sec at 0.5x guiding. The attached image shows the Dec through a cycle in each direction. The dump is from K3 using a ToUcam 840 in an ED80. The arrows indicate the start of a direction reverse. I find that PHD is having trouble accurately calibrating because of the issue.
|