ccdproc error

mora978 wrote on Feb 22, 2009

Hi all!

I have a problem with ccdproc when trying some flat correction:
ERROR: Cannot open image (006c.fit)

I have set imtype to "fit,noinherit" in my login.cl file.
ccdproc params:

 images = "@flatkorr_in.list"
(output = "@flatkorr_out.list")
(ccdtype = "")
(max_cache = 0)
(noproc = no)
(fixpix = no)
(overscan = no)
(trim = no)
(zerocor = no)
(darkcor = no)
(flatcor = yes)
(illumcor = no)
(fringecor = no)
(readcor = no)
(scancor = no)
(readaxis = "line")
(fixfile = "")
(biassec = "image")
(trimsec = "image")
(zero = "")
(flat = "flat.fits")
(illum = "")
(fringe = "")
(minreplace = 1.)
(scantype = "shortscan")
(nscan = 1)
(interactive = yes)
(function = "chebyshev")
(order = 1)
(sample = "*")
(naverage = 1)
(niterate = 1)
(low_reject = 3.)
(high_reject = 3.)
(grow = 0.)
(mode = "ql")

The input and output lists both contain 2 .fit filenames.
Filename 006c.fit - about the error says - is the name of one of the output files.
Before i was trying with the flat correction i did the bias and dark correction with the appropriate params, they did fine. I just can't get over with the flat correction.
Any suggestions?

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Stefano Berta wrote on Feb 22, 2009

HI,

try to check if the image 006c.fit already exists.

ccdproc does not overwrite. If it's there, imdel or imren it and run ccdproc again.

Stefano

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mora978 wrote on Feb 22, 2009

i know... this is not the source of error...

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mora978 wrote on Feb 22, 2009

i got it. iraf doesn't like filenames starting with a 0
anyway thanks for the reply.

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jchavez wrote on Feb 22, 2009

Hi, I am having this problem. I am using ccdproc to flat-field my images. I've successfully used ccdproc with only the flatcor switch turned on in several other directories. But for some reason I get the error that the output image doesn't exist (Of course! I expect ccdproc to produce it.)

unlearn
ccdproc.ccdtype=''
ccdproc.fixpix=no
ccdproc.overscan=no
ccdproc.trim=no
ccdproc.zerocor=no
ccdproc.darkcor=no
ccdproc.flatcor=yes
ccdproc.flat='Flatvd'
ccdproc.output='@outv.lst'
ccdproc @imgv.lst

Then it crashes saying it can't open "sa98va," which is the first image name in the outv.lst

I tried running ccdproc like this, to see if something was wrong with my list files
ccdproc.output='sa98va'
ccdproc boccd237.fits

I don't understand why this script has worked in a dozen other directories (from this and another observing run), but for this night it crashes.

I also tried getting a copy of "sa98va" from another night, but then of course, it said it couldn't overwrite it. So why doesn't ccdproc just make the flattened image I ask it to?

Thanks,
-Joy

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jchavez wrote on Feb 22, 2009

Oh, the first line of this script should read "unlearn ccdproc."

jchavez


unlearn
ccdproc.ccdtype=''
ccdproc.fixpix=no
ccdproc.overscan=no
ccdproc.trim=no
ccdproc.zerocor=no
ccdproc.darkcor=no
ccdproc.flatcor=yes
ccdproc.flat='Flatvd'
ccdproc.output='@outv.lst'
ccdproc @imgv.lst

Then it crashes saying it can't open "sa98va," which is the first image name in the outv.lst

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Mike Fitzpatrick wrote on Feb 22, 2009

Simple things first .... are you sure you have write permission in the data directory? Does the image already exist? Does e.g. CCDLIST on the input list work?

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jchavez wrote on Feb 22, 2009

Yes, I have permission in this directory. No, I don't have the output file already in the directory where I'm working. I have other versions from other observing nights, but I'm trying to flat correct the images from this particular night.

Yes, CCDLIST works on the input list. My problem with CCDPROC occurred whether I used input/output lists or just a single file. Either way, it said "Cannot open image (sa98.fits)", where 'sa98.fits' is what I'm trying to name the output file (which, if I used input and output lists, is the name of the first image in the output list). There is no sa98.fits already in the directory.

I've tried with other single files from the list as well. They start with 'p', 'n', 'g', and other letters, and none with '0', as was mentioned earlier in this thread.

Thank you for your help. It is always good to check the basics first.

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jchavez wrote on Feb 22, 2009

I have also tried this on another machine - still the same problem.

It happens in both PyRAF and IRAF.

Versions I've used:
PyRAF 1.9
IRAF V2.14
Python 2.5.4
(this is my computer)

PyRAF 1.8.1
IRAF V2.14
Python 2.5.4
(this is another server I have access to)

Thank you in advance for your help. It is important I get this last night reduced - it was a good observing night!

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Last post on Feb 22, 2009