Why won't emosaic combine my image masks?
In SAS v11.0 the format of the FITS files containing masks was changed.
This change wasn't propagated through to the emosaic task and so this task
doesn't recognise the new format.
If you want to combine EPIC masks, generated by emask, please apply the patch to your
SAS 11 installation using the patch file "esas-0.9.15-patch.tgz" corresponding to your operating system from
ftp://xmm.esac.esa.int/sasdev/Patches_to_SAS_11.0.0/.
Please follow the instructions in the "README.txt" file at that directory.
