a program that simulates astronomical images.
Check out the on-line documentation, the official web page, and the user forum.
The general SYNTAX is similar to that of SExtractor:
sky [<list_file>] [-c <Configuration_file>] [- ] ... to dump a default configuration file: sky -d to dump a default extended configuration file: sky -dd
- A list file is an ASCII file containing a list of objects that can be added to the simulated image. An example is provided in the config/sample.list file. Note that only stars (code = 100) and galaxies (code = 200) are recognized in this version.
- Keyword parameters given in the command line override those from the configuration file.
- If the list-file is given as unique argument, SkyMaker searches for a default configuration file called "sky.conf".
- SkyMaker creates 2 files in output: the image itself, and a catalog containing the objects it contains (with name toto.list if IMAGE_NAME was set to toto.fits).
- Currently, the following TYPEs can be used with the IMAGE_TYPE keyword: PUPIL_REAL, PUPIL_IMAGINARY, PUPIL_MODULUS, PUPIL_PHASE, PUPIL_MTF, PSF_MTF, PSF_FULLRES, PSF_FINALRES, SKY_NONOISE and SKY. The two latter keywords should be used for creating actual instrument images.
- A FITS header (any FITS image, or even an ASCII dump) can be provided through the IMAGE_HEADER keyword: simply replace "INTERNAL" by the file name. SkyMaker will then make a copy of this header for the simulated image, enabling the latter to be easily processed through your usual reduction tools.
- Thanks to Pascal Fouque, parameters describing common optical aberrations (including defocus, spheric, astigmatism and coma) have been included in the description of the pupil phase-plane. Their normalisation follow the ESO convention (equivalent angular diameter of a circle, in the focal plane, which encloses 80% of the PSF flux; this is generally slightly more than the FWHM). However the user is invited to check this normalisation, and report any unexpected result.
- If a SEED_* parameter is set to 0, the corresponding random generator is initialized to a "random" (function of time) value.
- Beware of large AUREOLE_RADIUS values: during the calculation of the image, a temporary border of <AUREOLE_RADIUS> pixels in thickness is added all around the image, and can significantly affect the computation time.