major issue platesolving after meridian flip

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kvz_astrophotography avatar
I've recently started using NINA to control my imaging sessions and I've been having this weird issue regarding my meridian flips. Essentially, once my mount executes the meridian flip and does a plate solve it slews back to where it was before the meridian flip essentially undoing the flip. once it's done this it does another plate solve and will then do a meridian flip again and I end up in this endless loop of meridian flip after meridian flip without making any progress.

for some reason, the only way I've been able to fix this problem is by unplugging the mount from my laptop, turning it off and on again, reconnecting everything, and then creating a new image sequence and starting from scratch. 

if anybody has any clue what could be my issue and how I could fix this please give me a shout, id really appreciate it thanks
Björn Arnold avatar
What mount do you have and by driver do you connect it?
What I would check is that you can tell NINA to use the pier side info from the mount driver. I could imagine that this might be an issue.

Björn
Claudio Tenreiro avatar
Hi, it is estrange, I did set up the meridian flip following closely the indications by Cuiv the lazy geek, and works perfectly, even I set up a sequence with two targets, that demands a first meridian flip while imaging the first target, and then  for the second target it had to go back, and after an hour it had to do again another meridian flip, and did it correctly, so twice on the same sequence, one in each target, moving back in between the two.
There is one issue that is mention by Cuiv, and also by Sean (Visible Dark), and it has to do with the mount limit for meridian flip, which has to be set up correctly, so if NINA fails, or crush, the mount will know when to stop without bumping in the pier. In some cases this instruction, if not correct, enters in conflict with NINA.
Now regarding the side of the pier, in the video by Cuiv, it is mention that, in some mounts, that instruction of the side may cause a problem, it is a kind that there is a conflict on which side really the scope is, in those cases it recommends to disable it and let the system to decide which side, but watch the videos to decide if it is your case or not.
CS !
Padraic Moran avatar
What have you set for 'Minutes after Meridian' in Options->Imaging? It may be worth increasing this, so that the target gets to move slightly farther west of the meridian before you platesolve.
Well Written Concise
Claudio Tenreiro avatar
Just to complement my answer, I did set up the meridian flip 6 minutes past meridian, and the limit 10 minutes past meridian, no side of the pier (It detect it by itself).
KIJJA JEARWATTANAKANOK avatar
Claudio Tenreiro:
Just to complement my answer, I did set up the meridian flip 6 minutes past meridian, and the limit 10 minutes past meridian, no side of the pier (It detect it by itself).

Totally agree.  This lag time allows centering on target run completely.
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