[AstroPy] Pywcs not reading transformation matrix correctly

Oliver King ogk@astro.caltech....
Thu Jul 26 12:21:48 CDT 2012


That fixed it - I guess that it was an already-squashed bug.

Thanks for your help.

Oliver

On Jul 26, 2012, at 10:15 AM, Oliver King wrote:

> This might be the reason:
> 0.0.dev1119
> 
> I'll try updating to the latest version.
> 
> On Jul 26, 2012, at 10:10 AM, Thomas Robitaille wrote:
> 
>> Which version of Astropy are you using?
>> 
>> import astropy
>> print astropy.__version__
>> 
>> I'm using the latest developer version, and it seems to be working:
>> 
>> CD_11  CD_12: -7.7588993045300006e-05 4.5042903792000001e-07
>> CD_21  CD_22: -3.9690360471000002e-07 -7.7631469153300006e-05
>> CRVAL    : 343.48506545599997 16.146689138399999
>> CRPIX    : 1094.26737976 1037.5606839899999
>> NAXIS    : 0.0 0.0
>> 
>> If you are using v0.1, could you try updating to the latest git
>> version to see if it was fixed?
>> 
>> Thanks!
>> Tom
>> 
>> On 26 July 2012 19:03, Oliver King <ogk@astro.caltech.edu> wrote:
>>> Hi JB,
>>> 
>>> The WCS does not have a RADECSYS keyword; the CTYPE is TAN-SIP. Here are all the WCS parameters (excluding the polynomial coefficients). This is an image which has had a WCS attached by the astrometry.net software.
>>> 
>>> CTYPE1  = 'RA---TAN-SIP' / TAN (gnomic) projection + SIP distortions
>>> CTYPE2  = 'DEC--TAN-SIP' / TAN (gnomic) projection + SIP distortions
>>> WCSAXES =                    2 / no comment
>>> EQUINOX =               2000.0 / Equatorial coordinates definition (yr)
>>> LONPOLE =                180.0 / no comment
>>> LATPOLE =                  0.0 / no comment
>>> CRVAL1  =        343.485065456 / RA  of reference point
>>> CRVAL2  =        16.1466891384 / DEC of reference point
>>> CRPIX1  =        1094.26737976 / X reference pixel
>>> CRPIX2  =        1037.56068399 / Y reference pixel
>>> CUNIT1  = 'deg     ' / X pixel scale units
>>> CUNIT2  = 'deg     ' / Y pixel scale units
>>> CD1_1   =   -7.75889930453E-05 / Transformation matrix
>>> CD1_2   =     4.5042903792E-07 / no comment
>>> CD2_1   =    -3.9690360471E-07 / no comment
>>> CD2_2   =   -7.76314691533E-05 / no comment
>>> IMAGEW  =                 2048 / Image width,  in pixels.
>>> IMAGEH  =                 2048 / Image height, in pixels.
>>> 
>>> Cheers,
>>> Oliver
>>> 
>>> On Jul 26, 2012, at 9:58 AM, Jean-Baptiste Marquette wrote:
>>> 
>>>> 
>>>> Hi Oliver,
>>>> 
>>>>> Is this a known bug? Is there a workaround or do I need to manually edit my FITS file headers?
>>>> 
>>>> What are your CTYPEn and RADECSYS ?
>>>> 
>>>> Cheers
>>>> JB
>>> 
>>> ------
>>> Oliver King
>>> Astronomy Department, Caltech
>>> +1-626-395-4197
>>> 
>>> _______________________________________________
>>> AstroPy mailing list
>>> AstroPy@scipy.org
>>> http://mail.scipy.org/mailman/listinfo/astropy
> 
> ------
> Oliver King
> Astronomy Department, Caltech
> +1-626-395-4197
> 
> _______________________________________________
> AstroPy mailing list
> AstroPy@scipy.org
> http://mail.scipy.org/mailman/listinfo/astropy

------
Oliver King
Astronomy Department, Caltech
+1-626-395-4197



More information about the AstroPy mailing list