Extracting 1D spectra using apall
Nick Devereux wrote on Jun 25, 2009
Frank,
Could you please post or send me an epar on apall for a simple
non-interactive onedspec extraction, 6 pixels wide.
I've run the task, it seems to work, but I get six lines of output
to do with trace. I don't know what trace is, or even if I need it.
What are the correct answers to alll the questions after (interac=
Thanks in anticipation
Nick
Could you please post or send me an epar on apall for a simple
non-interactive onedspec extraction, 6 pixels wide.
I've run the task, it seems to work, but I get six lines of output
to do with trace. I don't know what trace is, or even if I need it.
What are the correct answers to alll the questions after (interac=
Thanks in anticipation
Nick
Frank Winkler wrote on Jun 25, 2009
Hi,
If you know where you want to extract a 1-D spectrum from the same lines all across the image, then apall is overkill. You can do this very easily using blkavg:
cl> blkavg 2dfile[*,509:515] 1dfile 1 7 [option = average or sum]
will [average/sum] 7 lines centered at line 512.
For emission-line objects, especially, this can be a lot easier than trying to trace the aperture along the image using apall.
Good luck,
Paco
If you know where you want to extract a 1-D spectrum from the same lines all across the image, then apall is overkill. You can do this very easily using blkavg:
cl> blkavg 2dfile[*,509:515] 1dfile 1 7 [option = average or sum]
will [average/sum] 7 lines centered at line 512.
For emission-line objects, especially, this can be a lot easier than trying to trace the aperture along the image using apall.
Good luck,
Paco
Last post on Jun 25, 2009