Max, Thanks. That works and this looks really powerful, particularly the ability to measure multiple variables in a field and generate automatic reports. My only remaining comment is that I get strange timestamps:
ES UMa, -4713-11-24 12:00:00.000 UTC, G = 10.91 ± 0.11
-4713 is something like JD = 0. The FITS file I’m measuring includes the record:
DATE-OBS= ‘2021-05-25T22:53:18’ / Start time of stacked exposure
Nick.