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problem with darkcombine

cosmologist wrote on Feb 26, 2011

I don't know why I have this problem with darkcombine:



epar darkcombine

input   =                dark*  List of dark images to combine
(output =               Darkn1) Output dark image root name
(combine=              average) Type of combine operation
(reject =               minmax) Type of rejection
(ccdtype=                 dark) CCD image type to combine
(process=                  yes) Process images before combining?
(delete =                   no) Delete input images after combining?
(clobber=                   no) Clobber existing output image?
(scale  =             exposure) Image scaling
(statsec=                     ) Image section for computing statistics
(nlow   =                    0) minmax: Number of low pixels to reject
(nhigh  =                    1) minmax: Number of high pixels to reject
(nkeep  =                    1) Minimum to keep (pos) or maximum to reject (neg)
(mclip  =                  yes) Use median in sigma clipping algorithms?
(lsigma =                   3.) Lower sigma clipping factor
(hsigma =                   3.) Upper sigma clipping factor
(rdnoise=                   0.) ccdclip: CCD readout noise (electrons)
(gain   =                   1.) ccdclip: CCD gain (electrons/DN)
(snoise =                   0.) ccdclip: Sensitivity noise (fraction)
(pclip  =                 -0.5) pclip: Percentile clipping parameter
(blank  =                   0.) Value if there are no pixels
(mode   =                   ql)



:go



ERROR: Cannot open image (Zero)
  "ccdproc (ims, output="", ccdtype=ccdtype, noproc=no)"
     line 37: ccdred$darkcombine.cl
     called as: `darkcombine (mode=h)'

AnTaR3s wrote on Feb 26, 2011

I guess you have to set process to 'no'.
If it is set to 'yes', the procedure will call ccdproc to reduce the input frames before they are combined, where I think the image 'Zero' is required.

Last post on Feb 26, 2011