homogeneisation
try to put reso_arcmin or pixsize_arcmin everywhere to be consistant. Same for the name of the wcs (pathc_wcs, w, wcs_patch, ...) can we make something that: if pixsize has no unit then pixsize=pixsize*u.arcmin ? etc same pb for center=lonlat=lon, lat.... what is the best way to handle the coordinates ?
etc....