Jasem,

Thanks for this. I can now confirm my issue is user error or user misunderstanding. Hopefully, my comments below will be useful for others on this thread.

Using the standalone StellerSolver, I have computed the JNow centers of the first frame of the session, the last frame prior to the meridian flip and the first frame after the meridian flip. The difference between the first frame and last frame before the flip is 1'7" in RA and 5'41" in DEC. The difference between the first frame of the session and the first frame after the flip is 3" in RA and 2" in DEC.

There was another question on this thread about dithers. I dither every 5 frames for 5 pixels (~8 arc-seconds at my image scale) in a random manner. The number of frames before the meridian flip on this session was 179, giving approximately 35 dithers.

I guess one way to minimize drift issues would be to use the scheduler on a filter-by-filter basis. I can confirm that the post-meridian flip alignment with the scheduler was to the fits file given in the scheduler.

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