WCS alignment with a flip using v3.3.1

Posted by TAI on Jul 12, 2019; 6:39pm
URL: http://astroimagej.170.s1.nabble.com/WCS-alignment-with-a-flip-using-v3-3-1-tp1188.html

<tldr/> Align Stack using WCS doesn't seem to handle a flip

A sequence of FITS images were obtained with a GEM. About 75% through the sequence there was a flip. Before the images were imported in AIJ a third party software was run that plate solved each image and wrote WCS data to the FITS header.

Process -> Align Stack using WCS or apertures... with Use only WCS headers for alignment seemed to work though I'm not clear what the percentage refers to in the "Aligned_(30.8%)" window title.

Apertures are then placed in Multi-Aperture Measurements and after AIJ is told to do its thing lo, a Message window opens:

No signal for centroid in aperture T1 of image <the one taken right after a flip>. Multi-Aperture aborted.

Well, darn! Am I missing something in alignment process?

Thanks,
Jesse