Error when running “darkcombine”

Linas Petras wrote on Feb 14, 2008

For some reason I can't work out whenever I run a "darkcombine" task I get the following message:

ccdred> darkcombine *.FIT
ERROR: Cannot find or create calibration with nscan of 1
"ccdproc (ims, output="", ccdtype=ccdtype, noproc=no)"
line 37: ccdred$darkcombine.cl
called as: `darkcombine (input=*.FIT)'

ccdred> lpar ccdproc
       images = "@darklst"      List of CCD images to correct
      (output = "")             List of output CCD images
     (ccdtype = "dark")         CCD image type to correct
   (max_cache = 0)              Maximum image caching memory (in Mbytes)
      (noproc = no)             List processing steps only?\n
      (fixpix = yes)            Fix bad CCD lines and columns?
    (overscan = no)             Apply overscan strip correction?
        (trim = no)             Trim the image?
     (zerocor = yes)            Apply zero level correction?
     (darkcor = yes)            Apply dark count correction?
     (flatcor = yes)            Apply flat field correction?
    (illumcor = no)             Apply illumination correction?
   (fringecor = no)             Apply fringe correction?
     (readcor = no)             Convert zero level image to readout correction?
     (scancor = no)             Convert flat field image to scan correction?\n
    (readaxis = "line")         Read out axis (column|line)
     (fixfile = "badmap.pl")    File describing the bad lines and columns
     (biassec = "")             Overscan strip image section
     (trimsec = "")             Trim data section
        (zero = "Zero.fits")    Zero level calibration image
        (dark = "Dark.fits")    Dark count calibration image
        (flat = "FlatL1.fits")  Flat field images
       (illum = "")             Illumination correction images
      (fringe = "")             Fringe correction images
  (minreplace = 1.)             Minimum flat field value
    (scantype = "longscan")     Scan type (shortscan|longscan)
       (nscan = 1)              Number of short scan lines\n
 (interactive = no)             Fit overscan interactively?
    (function = "legendre")     Fitting function
       (order = 1)              Number of polynomial terms or spline pieces
      (sample = "*")            Sample points to fit
    (naverage = 1)              Number of sample points to combine
    (niterate = 1)              Number of rejection iterations
  (low_reject = 3.)             Low sigma rejection factor
 (high_reject = 3.)             High sigma rejection factor
        (grow = 0.)             Rejection growing radius
        (mode = "ql")

Any ideas ??

Linas

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Francisco Valdes wrote on Feb 14, 2008

Hi,

The message has to do with calibration of drift scan data. I see you have set scantype to longscan. This should not affect anything since you have scancor=no. But the logic can get complex and also depends on a header keyword.

... actually in looking at the code I see where it will look at scantype and if it is set to longscan it can cause a problem. So, unless you really are trying to work with drift scan data set scantype to "shortscan".

Yours,
Frank Valdes

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Francisco Valdes wrote on Feb 14, 2008

I may have been too hasty in thinking I understood the source of the error. However, try setting scantype to the default "shortscan" and see if the problem goes away.

Frank

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Last post on Feb 14, 2008