On Mon, 14 Jun 2004, David Berry wrote:
> The solution... modify the CRPIX1 value by subtracting the number of
> pixels in 360 degrees of longitude. So in your case change CRPIX1
> to
>
> CRPIX1 = 212464.628 - 360/CDELT1
> = -3535.37
>
> Changing CRPIX1 by 360/cdelt1 effectively changes changes the
> corresponding sky longitude by 360 degrees which has no effect on the
> displayed RA but results in the native spherical coords being in the right
> region [-180,+180].
>
> And Yes, FitsChan should probably do this automatically when it comes
> across this situation, but currently it doesn't.
>
Thanks Dave. Given that MSX are shipping files like this from their
archive, and there is presumably no chance of them fixing their headers
I think tweaking AST to support the MSX headers is the only sane thing to
do. [I'm getting lots of SCUBA users comparing with MSX data which is why
this keeps coming up]
--
Tim Jenness
JAC software
http://www.jach.hawaii.edu/~timj
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