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MX RA Backlash!
I finally may have figured out what has been wrong with my MX since day one. It's quite simple actually, but has taken me forever to get to this conclusion, no doubt due to the fact that I started off with this gear knowing essentially nothing. It's been reasonable for others, and for me, to assume that I simply have done something wrong. It's not an invalid assupmtion because I have made plenty of mistakes. But, underlying all of this is the fact that the mount just has not performed as advertised. Typical issues have been that no matter how well I am polar aligned, no matter how good my model, Protack simply has not worked reliably. Sometimes an unguided image might work only to have the next attempt completely fail. I don't mean just a little non-round, I mean totally smeared. And I've had guiding issues galore. Not just in guiding, but in even getting a guide star to show up in the center of a guiding graph once it has been selected!
In the process of using PEMpro to measure my PE I noticed in a very clear way what seems to be happening. If I slew to a star by moving the mount in a Westward direction I will get a beautifully straight line demonstrating perfect tracking in RA. However, if I slew to a star by moving the mount Eastward, all hell breaks loose and I will get drift of up to 10 arcsec over the next worm cycle. After 1 cycle the mount stabilizes and tracks beautifully, but not necessarily where one initiated the tracking. It might be 5+ arcsec away. This is pretty clearly demonstrated in the attached graphs from PEMpro. (PEC on, Protact off, +15 dec on meridian)
Does anyone reading this forum know what adjustment(s) might be off in my MX to cause this behavior? I've asked the question at SB but so far there is no response from the powers that be. The only things I've done to my mount are to replace the belts and adjust the cam-stop. The belt is not loose, and I believe not too tight either.
Thanks,
Peter
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