Celestron CGEM Meridian Flip Testing

 03/19/2026 -- No moon, but lots of clouds (more than predicted) makes the evening a good opportunity to play with the Celestron CGEM DX with the Nexstar+ version 4.22 hand controller and Indi/Ekos with regards to meridian flip.  Numerous / repeated disasters where the scheduler is paused ... in some cases for a half hour...other times for hours (never recovering) from repeated attempts to deal with meridian flip...almost always looking northward (since the deck is facing polaris). 

Read the Stellarmate guide on meridian flip... which while helpful, does not necessarily provide clear guidance specific to the Celestron...but it does illustrate how this process _should_ work.  Re-read the overview on the Celestron NexStar Indi driver...which is outdated and does not really deal with the interplay between driver, Ekos / Indi meridian settings and hand controller RA limits and meridian settings.  Also read the original Celestron User Manual for the CGEM, which does at least describe the hand controller settings -- including the RA limits and Meridian setting. 

Set up a test job after setting the hand controller RA limit to -1 degree (east and west limits).  Set the Flip if HA> 0.90 degrees in the Mount tab in Ekos.  This limit was hit... and Ekos waited for the current image to complete...then tried to initiate a flip.  This failed (the mount did not perform a meridian flip... no change in the "pier side" configuration (stayed West (pointed east))..with a 4 minute timer.  With this failed flip, alignment has to re-run (since the mount only sorta a little bit moved). Because of clouds...the alignment eventually failed and the camera collection (Sequence tab) aborted.  Tracking continued...and the timer for meridian flip continued to count down.  

In the Analyze tab, the Flip line showed MOUNT_FLIP_WAITING while the camera was completing collection of a light frame.  Then the Analyze tab Flip line showed MOUNT_FLIP_COMPLETED (even though the meridian flip actually failed).  Ultimately, did not find a configuration between Ekos and the CGEM that worked with regard to automatically performing a meridian flip. Most likely, the -20 degree default is the only setting likely to work (which is too far for the current hardware on the OTA to clear).

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