The task makethumbs reads an EPIC image, as well as optionally the source list file in each observation (as is included in the standard distribution of the pipe-line processing) and/or the external catalogue file in the format of the 2XMM catalogue, then outputs the thumbnail GIF images of the sources of user's choice. This task is mainly designed to produce a GIF image of each source or simply of a sky position so that the user can have a quick look at it.
This task has two processing modes: a single source (hence a single output file) and multiple sources (hence multiple output files). Only in the former case (single-source mode), users can specify the name of the discrete and complete output filename via the command-line parameter outfilename. If not, users can specify the root filename via gifroot and can control the rules of subsequent identifier via a few command-line arguments. If none is specified, the default filename(s) will be used.
Note that SAS tasks in default have the clobber setting activated. Therefore, unless users explicitly specify –noclobber (see Section 9 for an important note for –noclobber option), all the existing files with the identical names will be overwritten.
The basic input parameters for each source, such as its celestial coordinates, are read from the given source-list and/or the external catalogue in default. Only in the single-source mode, the position can be given via the command-line arguments, ra and dec. Some strings displayed in all the output GIF files can be given via several command-line arguments.
In determining the output filenames (unless a user specifies the discrete filename in the single-source mode), this task uses either or all of SRC_NUM (source number, which can be given via the command-line parameter srcnum in the single-source mode), DETID (meaning detection ID in the 2XMM catalogue) or SRCID (unique source ID in 2XMM), all of which are derived from either the input source-list or the given external catalogue.
Users can also make a fine control over the size and colour of the output GIF image, size and thickness of the hair-line cross in the image and strings of information displayed in the image.
See the following and Section 4 for detail.
