Our new correlator, ACSIS, by default generates cubes using a CAR
projection for the spatial axis. We are having a lot of trouble finding
applications that report the RA/Dec correctly for this projection at the
pole.
We have 3 example files:
near_pol_map.fits -> SIN projection
near_pol_map_car.fits -> CAR projection
near_pol_map_mer.fits -> MER projection
Available from
http://www.jach.hawaii.edu/~timj/proj.tar.gz
All have [1,1,1] set at 05:20:04.000 +89.59.00.000 6.914730e+11 Hz
[The spectral headers are not liked by AST v3 so I need to look into
that].
You'll be pleased to hear that GAIA does correctly report the
RA/Dec for CAR as the pole is crossed but the axis overlay is not quite
correct since it stops at +90 and does not draw in the top half of the
grid. I assume this is because of the RA discontinuity. Any chance that
could be fixed?
Also, the projection information is not reported in the
title (it's written as <null>) for all of the test images.
Jamie reports that the MER projection seesm to fail completely. FV
displays it fine but it seems to display as a SIN projection in GAIA. Is
AST meant to support MER?
--
Tim Jenness
JAC software
http://www.jach.hawaii.edu/~timj
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