mscrec/ccdproc & response

Mike Fitzpatrick wrote on Sep 24, 2010

Hello,

Apologies if I sent this to to wrong address, anyway I didn't find any other
candidate address (after a quick search in iraf.net).

Anyway, this post is about a bad combination of
mscred.ccdproc & twod.longslit.response
When reducing MEF-spectroscopy data I noticed that the
mcsred/ccdrpoc didn't do "anything" to the image.
Data: -internal flat (halogen lamp)
-science spectrum
Data reduction:
*bias subtraction & trim (all files)
*combining flats with mscred/flatcombine
*create a response image with twod.longslit/response

I found that if I use
*noao.imred.ccdproc / imarith (as image[1]) or mscred.mscarith
the image is reduced OK.
-However if I use mscred.ccdproc no correction was evident.

I found from the iraf.net-posts that CCDMEAN has been a bug in
mscred ( I can't remember the number, old one, solved by Frank Valdes),
so I removed the CCDMEAN keyword from the
(response) image header and after that mscred.ccdproc
worked as expected.

Is there any other way to "fix" this? I find mscred.ccdproc much more
user-friendly for the MEF-files than the noao.imred.ccdproc, however it
appears that I have to remember to remove the CCDMEAN-keyword
from the "response"-image.

By the way I'm using
"NOAO PC-IRAF Revision 2.12.2a-EXPORT Wed Jul 14 20:45:34 MST 2004"

[Mod Note: Forwarded from email]

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Last post on Sep 24, 2010