This looks like a bug but it's so basic that I'm almost surely going to end up facepalm. Almost.

Repeated observed behavior: Ekos plate solve will claim the telescope is aimed at the requested coordinates (within, say, 30 arcseconds) when in fact it is not. This is a problem with Ekos and not the external solver, astrometry.net in my case, because the correct coordinates of the test shot are written to the FITS header.

Example from last night: requested slew to Rho Capricorni by coordinates, 20h20m57.52s, -17:48:49.43, in the control panel. After settle, requested "capture and sync". Repeated until "capture and sync" reported error less than 30 arcseconds. This was clearly in error because there was no mag 4.8 star in the field of view ever. Captured the field anyway and checked the FITS header; the header reported location of center at 20h27m32.81s, -17:49:33.17. That's 1182 arcseconds difference in RA and 44 arcseconds difference in Dec!

Additional notes: system field of view somewhat narrow at 21' x 14'. Aperture somewhat wide at 25" so plenty of stars were captured in 1 second exposures. In another example with bright star target, Eta Pegasi, the star was captured in the first test shot and Ekos homed in on the star without difficulty. So the problem only seems to occur when the test field lacks a bright star for Ekos to home in on even though the plate solver has no difficulty.

Thoughts? I'm happy to provide access to FITS files. I'll try turn on logging tonight to see if that helps.

Thanks for reading.

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