markalot

Sorry, SNR. Look at the Guiding tab screenshot on this page: https://openphdguiding.org/man-dev/Advanced_settings.htm I have mass detection off as it kept losing the star when on, especially during poor seeing or transparency.

Have you tried just looping only to see what you can see? Have you turned off star mass detection (this caused all kinds of issues for me when on)? Have you bumped up the minimum star SNR for autofind? I had all kinds of issues when I started using a 2600 MC duo that I solved by increasing minimum DNR and turning off the star mass detection (I think it defaults to off). If the stars are actually vanishing (during looping) then I suspect the camera or the cable. I'd aim at a tree and loop during the day to see if its the camera or cable.

Howdy. I just retired my GTI to portable applications only. I was guiding and here's my experience watching how it tracks when hooked up to PHD2 (a guider that tracks errors). On some nights it tracks very well, and I suspect it's a balance, polar alignment, or tripod issues. I polar align using NINA 3 point alignment because I don't have a clear view of the north star. What I ended up doing was not guiding and reducing exposures to 30 seconds, which worked well for 90% of my subs, with a few still having star trails. Guiding for me usually increased errors due to declination backlash (play in the gears). It would over correct, swing wildly too far, then get into a back and forth loop. Not every night mind you! Do you know how to calculate what your error tolerance is? For example, if you are using a 360mm focal length with a 533 (3.76 pixel size) you have a tolerance of 2.15" per pixel (I'm relatively new but I think you'll notice any movement over half that value). That darn aluminum tripod has all kinds of weird flex, just push it around and see what I mean. I was never sure if my issues were all tripod or in the mount head itself, but I suspect the tripod was a lot of it. This also explains why some nights seemed different from others. Using PHD2 (looks like you're using ASIAir so you'd have to hook up a laptop) I can use guiding assistant to watch it guide without any corrections. The results were enlightening as you could see the declination wobble even though it should be fixed. Some nights had little wobble, others a lot of wobble. In reading up on it it seemed some solved this issue by purposely unbalancing so that there was a slight constant weight on one axis depending on which side of the pier you were on. Not sure this helps, but bottom line is reducing to 30 second subs should solve most of your issues, especially if you can turn off guiding (does ASIAir guide automatically)?