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I want to make sure the pointing refinement ran without problems for my data so that the coordinates in my images will be accurate to 0.2 arcsec or less.
Posted by Seppo Laine on 29 January 2009 12:07 PM
You can check the BCD header keyword USEDBPHF. If pointing refinement ran without problems, it should be set to "T". To see whether the superboresight pointing refinement ran successfully, you can look at the value of the BCD header keyword "BPHFNAME." It this filename starts with an "S", then the superboresight pointing refinement ran, if not, then it did not run. In superboresight pointing refinement the pointing refinement information from channels 1 and 2 is combined and applied to each channel, resulting in the most accurate available pointing values which are copied to the CRVAL1 and CRVAL2 BCD header keywords. You can always of course overlay the 2MASS catalog stars at the position of your images, for example with DS9 or Gaia, to check the pointing.