CGEM Alignment Problems
Posted 30 January 2011 - 01:06 AM
However, this all changed (seemingly for no reason) a few weeks ago. Now, all stars are WAY off, and they don't get any closer to center when I add calibration stars. My alignment stars are on the west of the meridian. Often, when I'm finished adding calibration stars from the east, when I try to slew to one of my original alignment stars on the west, it is further off than it started. This is REALLY frustrating, as any kind of ASPA is useless, and therefore imaging is out of the question. Before the problem started, I was using 6min exposures and not throwing any out.
I have tried all that I know to trouble shoot this. My date, time, location, and timezone are all correct. I have checked this about a million times. My mount is completely level. I have done 2 factory resets. I use a reticle eyepiece to center all of my alignment stars. When I add calibration stars, I try to keep them spread out. None of this has made the slightest difference. Even more weird, even with a completely garbage alignment, I was able to get the mount painstakingly polar aligned several days ago, and was able to keep 100% of 6 minute exposures over 2 hours! This makes me think that it is not a mechanical problem...
This is literally causing me to lose sleep, and has made me consider giving it all up. I have been doing everything the same as before (maybe even more carefully now), and the mount just won't point in the right direction!!!
Here's the last thing I can think of trying. In order to increase stability, I went from a foot mount on my 80mm EON to rings from ADM. If I remember correctly, this was right around the time the problems started. The rings are obviously a little larger than the OTA, and, despite my efforts to get the OTA aligned perfectly straight in the rings, I'm sure there is more cone error now than with the original foot mount. While I don't think there is a huge amount of cone error, could an increase in cone error cause ALL of my alignments to be off??? I thought the +4 calibration stars were supposed to take care of that...
Any suggestions??? I'm pretty desperate for help at this time. I really can't afford an expensive repair or Hypertune service. I know CGEM's have had their issues, but mine was absolutely perfect for the first almost-year-and-a-half of service. I would really appreciate any help.
Posted 30 January 2011 - 01:20 AM
Posted 30 January 2011 - 08:52 AM
Just as an aside, my 152mm refractor was unknowingly twisted in its rings when I first mounted it on my CG5 and my Gotos were all off. After I changed to a more secure wider dovetail that kept the OTA straight, the problem was solved.
Posted 30 January 2011 - 07:33 PM
Posted 31 January 2011 - 10:40 PM
Posted 31 January 2011 - 11:17 PM
Posted 01 February 2011 - 01:13 AM