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Hi, Mike et al---This problem may be well known to everyone, but I've found myself using ds9 and discovered it. When I display an image in ds9, it fails to pick up the WCS. But, if I load the same fits file into ds9 externally to IRAF (i.e., directly from the ds9 menu) the wcs comes up fine. (i.e., you see both x+y and RA and DEC
in the display)I've demonstrated that this is true both on the old (ds9 version 3.something) and the latest and greatest (version 4.0b7). It's true both on my Linux installation and on my Mac OSX systems.Finally, I talked to fans of DS9 (well, OK, Dave Silva) and he says that he has the same issue: no WCS in DS9 if he displays the image from IRAF, but WCs is there if loaded via the DS9 menu.---phil

Hi Phil,It is a well known problem and something SAO will have to one day fix. When you load an image standalone, DS9 reads the header to get the WCS. When you display from IRAF, what gets sent in the WCS packet is the path to the image. In XImtool this path is used to open the image the read the WCS and get pixel values, in DS9 it is used to decorate the window. People have said, "why not send the whole header"....we could, but the problem would remain until DS9 is changed to make use of [b:3c11d8b5fe]whatever[/b:3c11d8b5fe] information is sent. SAO is aware of the problem, for the moment there is no workaround other than to load standalone.Note that IMEXAM is still able to read the WCS from a DS9 display (via the 'x' key with the wcs=world parameter set) since it also has access to the image and cursor.Cheers,
-Mike

OK, that last statement was key. Thanks!!!
---phil

Is there a way to get the IRAF display command to run something like xpaset?

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Roland B. Roberts, PhD RL Enterprises Brooklyn, NY

No, run xpaset instead of display if that's what you want to do.-Mike