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Is there a way to view a raw spectrum profile in ISIS? I recently had an oversaturated fully processed spectrum which had an EW way too low and the reason was saturated pixels. You certainly can check the pixel rows in ISIS calibration panel which I went back and did so I figured it was most likely the cause, but I had to view the profiles of individual subframes in another program to actually see the flux cut off at the top of the emission peak which is the conclusive evidence. My question then is there a way to do that in ISIS?

Thank you


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Hi Dave,


One way I have been using to do that is to create fake master files: I take a spectrum image and, say in Iris, I create a fake offset where all pixels are set to 0. For the dark, I set all pixels to, say 100. And for the flat, same thing at say 1000 level. You must make sure that the fits headers of these fakes files include the date_obs and exptime keywords (I use AstroImageJ to update the headers if these keywords are missing). The date doesn't matter, of course, but make sure that the exptime make sense (for instance, 0.001 for the offset, 1 for the flat, and a linger value than the spectrum exposure time for the dark). Then, in Isis, I run the normal process, with the fake masters, all the way to the profile section.


I hope that this will be helpful.



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