Monday, September 15, 2008

Importing AIPS images into IRAF

Here is a question from reader donkeypuncher:

I'd like to use IRAF to do some analysis on images produced in AIPS. Alas, I am unable to open in IRAF the FITS files output by AIPS (task FITTP). I get this simple, non-informative message when I attempt to use the IRAF task display:

ERROR: Cannot open image (IMAGE.FITS)

I'm guessing it's a format issue, because I have no problem loading in ds9. Any ideas?

BTW, I like the site, thanks for your contributions!

My guess at an answer can be found if you click below..

I think that IRAF needs and expects the '.fits' suffix to be in all small letters. Try changing your image name to 'image.fits' and see if that helps.
Also-- something else I've noticed is that optical software often freaks out at the small pixel values in AIPS images (For example, are your pixel values on the order 10^-3 to 10^-6?). Once you get your image into IRAF, you might want to try multiplying your entire image by some large constant, say a million, using imarith. This could potentially save you headaches.


amanda said...
This comment has been removed by the author.
DonkeyPuncher said...

That's ridiculous, but it worked! Thanks for the help.