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11 November 2023 at 5:23 pm
#620120
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Participant
I’m no expert, but I don’t recall seeing A_ORDER, AP_ORDER, CTYPE1/2 or CRPIX1/2 in any FITS file that I had not plate solved. I think they all relate to parameters defining how the x/y pixel location is related to the RA/Dec value associated.
Its a polynomial, usually, so the comments about polynomial order are suggestive. 🙂
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This reply was modified 8 months, 2 weeks ago by
Grant Privett.