The procedures to reduce WIRCam images are available on the private svn repository:

wsvn/index/private/software/subsky/.

You can download it as a tarball from the svn repository, or checkout it directly in a svn work directory using

$ svn checkout svn+ssh://terapix.iap.fr/private/software/subsky.

The directory subsky contains
 subsky.pl: the perl script for sky subtraction.
 config: the directory collecting the configuration files for TERAPIX software. WARNING: this directory contains all configuration files used during WIRCam processing, for processing steps strongly dependent on image properties copy them outside the SVN directory and modify them without committing.
 c_scripts: the directory collecting C programs used in the execution of the main script and others useful during the processing chain.
 imcopy.pl: an optional procedure to RICE-decompress images.
 qfits.pl: an optional procedure to apply qualityFITS.
 preparesub.pl: a perl script to flag zeroes in *s.fits image sky-subtraction, to link weight maps and external headers.
 slistbuild.x: a shell script to prepare sub and s list from the p ones.
 detar.x: a shell script to de-archiving qualityFITS results (if they had been produced using the do-tar option in qfits.pl).
 qfits1.x: an example of shell script for the submission of qfits.pl using condor.
 subsky.x: an example of shell script for the submission of subsky.pl using condor.
 sgsep.pl: a Henry Joy McCracken perl script for star galaxy separation.
 smmacro: a directory collecting useful SM macros; a subdirectory galaxy_counts contains galaxy counts from the literature in 2MASS-like filters. WARNING: SM macros are strongly dependent on image properties copy them outside the SVN directory and modify them without committing.

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No configuration file is provided for subsky.pl.

Assuming that you downloaded the svn directory in your home directory (/home/nis/you/), you can run the script just using the command line

where <image_list> is the list of images you want to subtract.

Before starting the procedure:
 build input image list, selecting adjacent (in time and space) exposures (you can use listfile a C program available in the c_script ditrectory.);
 if you start a second pass subtraction, link in the directory the external headers and the weight maps you used for preliminary stacking as image.head and image_weight.fits, if image.fits is the name of the image you want to subtract (you can use link.pl provided in this distribution).

Subtracted images will be called image_sub.fits

The available options are:
 the number of input image extensions, -N or --n-exten (mandatory);
 the number of images to use in building sky frame, -n or --n-images (mandatory);
 the suffix of input weight maps, --inweight-suffix (optional);
 the suffix of output weight maps, --outweight-suffix (mandatory);
 the input bad pixel mask, -M or --mask (mandatory);
 the detection threshold to mask out objects, --threshold (optional, default is 1.);
 selection of second pass subtraction, --pass2;
 stack on which masked are built, -I or --image (mandatory with pass2 option);
 its weight map, -W or --weight (mandatory with pass2 option);
 creation of masks disabled, --disable-mask;
 production of sky-frame and subtraction disabled, --disable-sky;
 selection of guide crosstalk masking, --guide-on;
 number of parallel mask production, -T or --n-thread (optional, default is 1);
 path for TERAPIX software configuration files, --conf-path (mandatory, to be set to /home/nis/you/subsky/config if default configuration is used);
 path for C scripts, --script-path (mandatory, to be set to /home/nis/you/subsky/c_scripts if default path is used);
 option to do not delete sky-frames, --debug (optional, sky-frames are deleted by default);
 selection of VERBOSE_TYPE for TERAPIX software, --verbose (optional, default is QUIET);
 e-mail adress to notify the end of the processing, --mail (optional).

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No configuration file is provided for qfits.pl.

Assuming that you downloaded the svn directory in your home directory (/home/nis/you/), you can run the script just using the command line

where <image_list> is the list of images you want to 'qfitsed'.

The available options are:

 the suffix of input weight maps, --inweight-suffix (optional);
 path for TERAPIX software configuration files, --conf-dir (mandatory, to be set to /home/nis/you/subsky/config if default configuration is used);
 path for calibration images (flats and bad pixel masks), --calib-dir (mandatory);
 selection of quality assessment on double pass subtracted images (some flags on input images are different), --pass2;
 selection of output format in tar archive (useful only for condor submissions), --do-tar;
 e-mail adress to notify the end of the processing, --mail (optional).

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For more details and examples see the WIRCam Documentation and the step-by-step WIRCam data reduction article.