Ame
imstack [\,-vi\/][\,-o filename\/][\,-n num\/] \,file1.fits file2.fits \/... \,filen.fits\/
Stack FITS or IRAF images into single FITS image
or : imstack [-vi][-n num] @filelist -i: Do not put FITS header in output file -n num: Use each file this many times -m: Write IRAF multispec file -o name: Output filename -v: Verbose -x root: Make first file root, others extensions