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Last modified: 26 October 2016

URL: http://cxc.harvard.edu/ciao/bugs/arfcorr.html

Bugs: arfcorr


Table of Contents

Caveats

Bugs


Caveats

ARF correction may be incorrect for small regions

When using an input arf file and region, the input infile image should be binned at a resolution smaller than the region size. For example, if using a circle with a 1 ACIS pixel radius (0.5"), the infile image should be binned at subpixel resolution.

Using an input image with a binsize comparable to the size of the region does not provide arfcorr enough pixels to compute an accurate model of the PSF and therefore the corrections to the ARF become inaccurate.


Bugs

Tool does not add a history entry to the header.

The tool does not add a history entry to the output file header, which means the dmhistory tool cannot be used to recall the command.


Last modified: 26 October 2016
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