ASIAIR Guiding gone haywire tonight

[Knmurphy1]

Hi folks, I went out to image M101 tonight and I couldn't get my guiding working with the ASIAIR Plus and my ASI120MM guide camera (with 50mm/F4 guide scope). I have used it many times over the past two years with no issues. I restarted the whole setup several times with the same results. The odd thing is, I tried switching the guiding on the ASIAIR to the main telescope (Explore Scientific 102 ED) and ZWO183MC camera and it began guiding normally. I even took a 30 second image through the guide scope of M101 and everything was normal. Hope someone has some advice on this. Thanks for reading. See screenshot.

[michael8554]

Not much info on your setup and settings.

Did you PA ?

Did it Calibrate successfully ?

Did you reset the focal length after swapping OTA's ?

Could be:

Pier side wrong

Huge PA error

Guidecam rotated since last Cal.

Michael

[Elp]

What does the calibration graph look like and where in the sky did you calibrate?

[Knmurphy1]

Hi guys, Thanks for the comments. I didn't re-calibrate from whatever I did last (months ago when it was last clear). I'm still very much a novice. PA and focal lengths were correct Michael, calibration wasn't.  Guide cam was probably rotated also since it was removed. Comments have been very helpful, thanks.

[Elp]

Usually even if I'm imaging the next night with the rig intact I'll briefly look over the guide cam feed to make sure it's tracking stars correctly. Any sort of movement can potentially move things if by gravity, cables catching, clamping not being sufficient etc. You can't assume your rig is foolproof, in fact using automation it's very important to check and recheck everything, especially if it's going to be a long session. If your guidecam or guide scope has moved in any way it's usually good practice to recalibrate, and try to calibrate somewhere near the celestial equator.

[Giles_B]

As a fellow beginner, problems with guiding sound very familiar to me

Mine have stemmed from -

PA being out (from the mount being knocked - who knew this could lead to huge errors...)

RA being unbalanced (due to change of target / scope orientation revealing Z-axis problems...)

Calibration (I now routinely calibrate at the start of guiding)

 

[michael8554]

If your setup is not completely permanent then, a fresh Cal every night takes very little time.

And a good Cal is fundamental to good guiding.

Michael