Problem combining mosaic images in V2.14.1
djbard wrote on Apr 28, 2010
Hello,
I'm trying to combine several mosaiced darks where one of the segments [8] is broken and therefore filled with zero-valued pixels. When I try to combine them using darkcombine in mscred using iraf V2.14.1 I get errors:
mscred> darkc @dark.lst out=dark
.... *snip*........
Apr 28 11:47: IMCOMBINE
combine = median, scale = exposure, zero = none, weight = none
reject = minmax, nlow = 0, nhigh = 1
blank = 0.
Images
1s.DARK.0853.fits[8]
1s.DARK.0854.fits[8]
Output image = dark[inherit], ncombine = 2
ERROR: floating point divide by zero
"pclip=pclip, grow=0)"
line 49: ccdred$darkcombine.cl
called as: `darkcombine (input=@dark.lst, output=dark)'
mscred> imstat 1s.DARK.0853.fits[8]
# IMAGE NPIX MEAN STDDEV MIN MAX
1s.DARK.0853.fits[8] 1057471 0. 0. 0. 0.
I presume the error is with the blank segment [8] but if I set all the pixels in this segment to non-zero (using imreplace) I get the same error. Any ideas? I should note that I have iraf V2.14 installed elsewhere and I don't have this problem when I do the same thing there. [size=9:6ce99b397e](unfortunately I don't have the disk space there to process all the files I need!)[/size:6ce99b397e]
cheers,
Debbie
Details:
My files can be found here:
http://tinyurl.com/36gq337
mscred> epar mscred
I R A F
Image Reduction and Analysis Facility
PACKAGE = clpackage
TASK = mscred
(pixelty= real real) Output and calculation pixel datatypes
(verbose= yes) Print log information to the standard output?
(logfile= logfile) Text log file
(plotfil= ) Log metacode plot file
(backup = once) Backup data (none|once|all)?
(bkuproo= Raw/) Backup root (directory or prefix)
(instrum= mscred$lib/mosaic.dat) CCD instrument file
(ampfile= amps) Amplifier translation file
(ssfile = subsets) Subset translation file
(im_bufs= 0.065536) Image I/O buffer size (in Mbytes)
(graphic= stdgraph) Interactive graphics output device
(cursor = ) Graphics cursor input
(version= V4.8: May 11, 2004)
(mode = ql)
($nargs = 0)
mscred> epar darkc
I R A F
Image Reduction and Analysis Facility
PACKAGE = mscred
TASK = darkcombine
input = @dark.lst List of dark images to combine
(output = ) Output dark image root name
(combine= median) Type of combine operation
(reject = minmax) Type of rejection
(ccdtype= ) CCD image type to combine
(process= no) Process images before combining?
(delete = no) Delete input images after combining?
(scale = exposure) Image scaling
(statsec= ) Image section for computing statistics
(nlow = 0) minmax: Number of low pixels to reject
(nhigh = 1) minmax: Number of high pixels to reject
(nkeep = 1) Minimum to keep (pos) or maximum to reject (neg)
(mclip = yes) Use median in sigma clipping algorithms?
(lsigma = 3.) Lower sigma clipping factor
(hsigma = 3.) Upper sigma clipping factor
(rdnoise= 12) ccdclip: CCD readout noise (electrons)
(gain = 2) ccdclip: CCD gain (electrons/DN)
(snoise = ) ccdclip: Sensitivity noise (fraction)
(pclip = -0.5) pclip: Percentile clipping parameter
(blank = 0.) Value if there are no pixels
(mode = ql)
I'm using iraf V2.14.1 installed on a linux box:
NOAO/IRAFNET PC-IRAF Revision 2.14.1 Mon Sep 15 10:12:05 MST 2008
This is the RELEASED version of IRAF V2.14 supporting PC systems.
I'm trying to combine several mosaiced darks where one of the segments [8] is broken and therefore filled with zero-valued pixels. When I try to combine them using darkcombine in mscred using iraf V2.14.1 I get errors:
mscred> darkc @dark.lst out=dark
.... *snip*........
Apr 28 11:47: IMCOMBINE
combine = median, scale = exposure, zero = none, weight = none
reject = minmax, nlow = 0, nhigh = 1
blank = 0.
Images
1s.DARK.0853.fits[8]
1s.DARK.0854.fits[8]
Output image = dark[inherit], ncombine = 2
ERROR: floating point divide by zero
"pclip=pclip, grow=0)"
line 49: ccdred$darkcombine.cl
called as: `darkcombine (input=@dark.lst, output=dark)'
mscred> imstat 1s.DARK.0853.fits[8]
# IMAGE NPIX MEAN STDDEV MIN MAX
1s.DARK.0853.fits[8] 1057471 0. 0. 0. 0.
I presume the error is with the blank segment [8] but if I set all the pixels in this segment to non-zero (using imreplace) I get the same error. Any ideas? I should note that I have iraf V2.14 installed elsewhere and I don't have this problem when I do the same thing there. [size=9:6ce99b397e](unfortunately I don't have the disk space there to process all the files I need!)[/size:6ce99b397e]
cheers,
Debbie
Details:
My files can be found here:
http://tinyurl.com/36gq337
mscred> epar mscred
I R A F
Image Reduction and Analysis Facility
PACKAGE = clpackage
TASK = mscred
(pixelty= real real) Output and calculation pixel datatypes
(verbose= yes) Print log information to the standard output?
(logfile= logfile) Text log file
(plotfil= ) Log metacode plot file
(backup = once) Backup data (none|once|all)?
(bkuproo= Raw/) Backup root (directory or prefix)
(instrum= mscred$lib/mosaic.dat) CCD instrument file
(ampfile= amps) Amplifier translation file
(ssfile = subsets) Subset translation file
(im_bufs= 0.065536) Image I/O buffer size (in Mbytes)
(graphic= stdgraph) Interactive graphics output device
(cursor = ) Graphics cursor input
(version= V4.8: May 11, 2004)
(mode = ql)
($nargs = 0)
mscred> epar darkc
I R A F
Image Reduction and Analysis Facility
PACKAGE = mscred
TASK = darkcombine
input = @dark.lst List of dark images to combine
(output = ) Output dark image root name
(combine= median) Type of combine operation
(reject = minmax) Type of rejection
(ccdtype= ) CCD image type to combine
(process= no) Process images before combining?
(delete = no) Delete input images after combining?
(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= 12) ccdclip: CCD readout noise (electrons)
(gain = 2) ccdclip: CCD gain (electrons/DN)
(snoise = ) ccdclip: Sensitivity noise (fraction)
(pclip = -0.5) pclip: Percentile clipping parameter
(blank = 0.) Value if there are no pixels
(mode = ql)
I'm using iraf V2.14.1 installed on a linux box:
NOAO/IRAFNET PC-IRAF Revision 2.14.1 Mon Sep 15 10:12:05 MST 2008
This is the RELEASED version of IRAF V2.14 supporting PC systems.
djbard wrote on Apr 28, 2010
For the record, the problem was that the site I'm working at had mscred V4.8 installed, which is evidently incompatible with iraf V2.14.1. By updating to mscred V4.9 this problem went away and I could get on with my mosaic data reduction.
cheers,
Debbie
cheers,
Debbie
Last post on Apr 28, 2010