Here are some examples of using
stilts tskymap in=iras_psc.fits lon=RA lat=DEC out=iras_map.csv
stilts tskymap in=iras_psc.fits lon=RA lat=DEC tiling=hpx6 ocmd='healpixmeta -csys C' ofmt=fits-healpix out=iras_map.fits
ofmt=fits-healpix, which writes a FITS file following the HEALPix-FITS convention. An additional filter "
healpixmeta -csys C" is also supplied here: this indicates that the HEALPix pixels in the output file are to be considered in the Celestial (=equatorial) sky system. If this is not done, Aladin assumes the coordinate system to be Galactic and will align the results incorrectly on the sky.
stilts tskymap in=2mpz.fits icmd='addskycoords fk5 galactic ra dec glon glat' lon=glon lat=glat tiling=hpx6 cols='jCorr-hCorr hCorr-kCorr jCorr-kCorr' combine=median count=false complete=true out=2mpzColors.fits
addskycoordsfilter has been used so that the grid is laid on the sky with galactic coordinates. Setting
complete=trueguarantees that a row is written to the output file for every sky pixel, including empty ones. Note in this case that the output format is not specified explicitly, so it will be inferred from the filename, to be "normal" FITS, rather than
healpix-fits. The output data will still be present, but external applications may not automatically identify the pixel column.
stilts tskymap in=tgas_source.fits tiling=hpx7 lon=l lat=b count=false cols=phot_g_n_obs combine=sum-per-unit perunit=arcmin2 ofmt=fits-healpix ocmd='healpixmeta -csys G' out=obs-density.fits
phot_g_n_obsvalues from the input table that fall into each tile and applying a suitable scaling factor. The grid coordinate system is explicitly labelled as Galactic.
stilts tskymap in=gums_lmc.fits lon=alpha lat=delta tiling=hpx14 complete=false omode=count
complete=false, only rows for non-empty pixels are included in the output table. Then, since the output mode is
count, these rows are just counted, discarding the pixels themselves, giving the number of level-14 healpix pixels touched by the sources in this input file. Note this is not necessarily the most efficient way to calculate coverage information.