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Fast coordinate conversion with ds9

Fast and easy conversion of a .reg file with image coordinates (x,y positions) to sky coordinates (RA,Dec;sexagesimal):

ds9 image.fits -regions load input_imageCoordinates.reg -regions system wcs -regions skyformat sexagesimal -regions save outout_skyCoordinates.reg -exit

with automatic exit of the program!

Thanks to Alexandros M. for providing some examples!

References:
[1] ds9: http://ds9.si.edu/site/Home.html
[2] ds9 command list: http://ds9.si.edu/ref/command.html

DS9 refuses radians as input

At the region file help page of ds9 we read that we can define position arguments in a region file by placing the numbers along with the right character, e.g. 17.845d for degrees, 16.234p for pixels.

Even though that radians are stated to be working (by placing the r character, like 12.123r), that finally DOES NOT WORK !!

I cannot understand why this happens (I even mailed them but without any answer yet!) and the only option is to convert radians to degrees before actually use them.