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FITS image opens in DS9 but not IRAF

ofwolf42 wrote on Feb 23, 2011

When I open the files from DS9 directly it opens and I see exactly what I'd expect but when I try and open it from IRAF using the display function the image displayed on DS9 is junk/noise with no resemblance to the original image. The image has undergone a lot of conversions and I assume this is the source of the error. But I'm hoping that it's fixable since I can view the file perfectly outside IRAF. Could it be a header issue or just an artifact of the conversions?

To be specific about the conversions, it was originally from an ogv video, which was converted to an avi (using mencoder) then to a series of jpeg images (with Avidemux) then to fits images (using the linux "convert" function). So there are a number of places it may have gone wrong. I have used this process before except for using mencoder, I usually work with avi and mpg which Avidemux can read but I needed to convert the ogv.

Mike Fitzpatrick wrote on Feb 23, 2011

Please post a sample image to the anonftp at ftp://iraf.noao.edu/pub and reply here with the IRAF and OS version you are using.

ofwolf42 wrote on Feb 23, 2011

I just up loaded it as "DS9-IRAF.png", the left side of the image is what I see when I double click the file and the right side is what I get when I use IRAF's display function.

I'm using IRAF version 2.14.1 and ubuntu 10.04.

Mike Fitzpatrick wrote on Feb 23, 2011

I know a picture's worth a thousand words but a picture of the problem file isn't nearly as helpful as the problem file itself. Please upload the FITS file causing problems.

ofwolf42 wrote on Feb 23, 2011

Also put up a sample image as 14.fits (having realized that's most likely what you wanted, my apologies)

Mike Fitzpatrick wrote on Feb 23, 2011

I think the problem is just that you're using the default imt512 frame buffer so you're only seeing the central 512x512 pixels and the star is being clipped from the display. Try doing

cl> reset stdimage = imt800


and then redisplay the image. Set the DISPLAY task 'contrast' parameter to 0.0 and you'll use the full 8-bit data range in the scaling.

ofwolf42 wrote on Feb 23, 2011

Thank you very much for your help! That worked perfectly!

Last post on Feb 23, 2011