HEADAS help file

NAME

uvotunicorr

USAGE

uvotunicorr obsfile=<filename> reffile=<filename> obsreg=<filename> refreg=<filename>

DESCRIPTION

This tool performs a user guided aspect correction on a sky image.

The reference sky image (reffile) must have WCS keywords. The tool ds9 can be used to retrieve a valid reference image by using the STSci DSS I/II server.

The region files (obsreg and refreg) can be created by drawing regions in a tool like ds9. The number of regions in obsreg and refreg must be equal. The obsreg and refreg can also contain lines of the form

	radec: 286.2, -8.16

for known positions.

PARAMETERS

obsfile [filename]: Sky image to correct.
reffile [filename]: Reference sky image.
obsreg [filename]: Region file for observed objects (obsfile).
refreg [filename]: Region file for reference objects (reffile).
(maxresid = 1.0) [real]: Maximum residual to allow after correction [arcsec]. If applying the correction quaternion leaves a larger separation than this between any of the observed and referencec positions, the correction will not be applied. Note that the residuals are calculated based on applying the quaterion, but with rotate=no, the residuals in the corrected image may still exceed maxresid.
(rotate = no) [boolean]: Allow adjusting image rotation?
(history = yes) [boolean]: Write history keywords?
(cleanup = yes) [boolean]: Remove temporary files?
(chatter = 2) [integer: 1-5]: Standard HEAdas chatter parameter.

EXAMPLES

The following example illustrates running uvotunicorr

      uvotunicorr obsfile=some.img+3 reffile=dss.img \
			obsreg=some.reg refreg=ref.reg

LAST MODIFIED