The ISAAC instrument exhibits field distortion
amounting to
2.5 pixels in the corners of the detector. If not corrected, mosaics
with large dithers have multiple images in the overlap regions.
Therefore recipes resample the image applying the published polynomial
mapping. This correction also improves the registration. The sky
co-ordinates are also corrected for the distortion.
[ISAAC/_DEFINE_DISTORTION_TRANSFORMATION_,
ISAAC/_APPLY_DISTORTION_TRANSFORMATION_]
ORAC-DR -- imaging data reduction