Hi Nikolay,
In other words, all processing should be independent of the Coordinate origin settings. I am right?
it's very dangerous
You are completely right in both affirmations. Unfortunately, however, this is not how the FITS format works. The coordinate origin settings are not intended to control how a FITS image is represented; they are necessary to tell the application how a FITS file has been
generated, so it can be loaded with the correct orientation.
Most professional image acquisition systems generate FITS files with the bottom-to-top, left-to-right orientation. This means that the first row of pixels is stored at the
end of the HDU data block in the .fit file.
All amateur equipment generate FITS files with the top-to-bottom, left-to-right orientation. This means that the first row of pixels is stored at the
beginning of the HDU data block in the .fit file.
I added the coordinate origin setting to the FITS file format support to let PixInsight adapt to both situations. Most imaging software does not have this flexibility, and only supports the amateur convention, but PixInsight does.
Since the initial versions of PixInsight, the default FITS orientation has been bottom-to-top, left-to-right, i.e. the professional convention. Although this was a purist's choice, it definitely was a strategic error, since perhaps the 95% of FITS files loaded in PixInsight follow the amateur convention.
So in the next version 1.8 of PixInsight the default FITS orientation is top-to-bottom, left-to-right (amateur). This will remove all practical problems since PI will behave out-of-the-box just as expected by most users. It will cause us a few problems with professional users, but nobody's perfect
