View on GitHub

IRAF Community Distribution

IRAF maintained by the community

Home | Installation | Packages | X11IRAF | PyRAF | Forum

zerocombine problem

edmeades wrote on Oct 24, 2007

I have a user who is trying to use zerocombine, but it doesn't seem to want to open the images.

When she or I run the zerocombine task, this is what we get:
zerocombine
List of zero level images to combine: ccd0009c1.fits,ccd0008c1.fits
ERROR: No images to combine
"pclip=pclip, grow=0)"
line 47: ccdred$zerocombine.cl
called as: `zerocombine ()'

I tried fiddling with the ccdtype parameter, but that didn't help.

Any ideas?

Thanks again!

Mike Fitzpatrick wrote on Oct 24, 2007

Setting the 'ccdtype' parameter to a null string (i.e double quotes like "") will force the input list to be processed as-is. Otherwise, things depend on the cctdype header keyword and/or the task parameter. Note that SETINSTRUMENT can be used to modify the image header keyword translations.

-Mike

edmeades wrote on Oct 24, 2007

Okay, I tried that and I get this:
ccdred> zerocombine
List of zero level images to combine: ccd0008c1.fits,ccd0009c1.fits
ERROR: segmentation violation
"pclip=pclip, grow=0)"
line 47: ccdred$zerocombine.cl
called as: `zerocombine ()'

I should be using a comma to separate the filenames, right?

Mike Fitzpatrick wrote on Oct 24, 2007

A comma to separate files is correct. Can other tasks like IMSTAT or IMHEAD open the images properly? Any chance of a permissions problem or a malformed FITS file?

-Mike

edmeades wrote on Oct 24, 2007

The odd thing is that another of my users can do the zerocombine on the images, so there's some environment setting that I just don't know.

We tried copying the iraf environment from the user that works to the one that doesn't, but that didn't work, either.

I verified that everything else works okay:

ccdred> imstat ccd0008c1.fits
# IMAGE NPIX MEAN STDDEV MIN MAX
ccd0008c1.fits 8785920 1058. 47.02 1007. 11896.
ccdred> imhead ccd0008c1.fits
ccd0008c1.fits[2112,4160][ushort]: bias

meat[~/iraf] ls -lah
-rw-r--r-- 1 edmeades uucp 17M 2007-10-24 13:12 ccd0008c1.fits
-rw-r--r-- 1 edmeades uucp 17M 2007-10-24 13:12 ccd0009c1.fits

I also added execute permission, but that didn't help.

The files open in ds9, and don't look obviously corrupted, but I'm not an astronomer.

Francisco Valdes wrote on Oct 24, 2007

Note that zerocombine has the option to call ccdproc before combining. So it have something to do with that task. You should usually include task parameter listings when presenting a problem. There are various ways to narrow down the problem when a script task is involved. One is to type "d_trace" to dump out a lot of debugging info. The main useful bit is that lask task call, with all its parameters, before the crash occurs. You type d_trace again to stop the output.

One comment, because I recently dealt with this, is that copying another user's environment needs to include the uparm directory as well.

I can try and help further with a parameter listing and possibly the d_trace info about the last executable run.

Frank Valdes

Jason Quinn wrote on Oct 24, 2007

I'm having the exact same problem the original poster did with zerocombine. It does not seem to understand the IMAGETYP keywords anymore.


PACKAGE = ccdred
   TASK = zerocombine

input   =                zero*  List of zero level images to combine
(output =                 Zero) Output zero level name
(combine=              average) Type of combine operation
(reject =               minmax) Type of rejection
(ccdtype=               bias) CCD image type to combine
(process=                   no) Process images before combining?
(delete =                   no) Delete input images after combining?
(clobber=                   no) Clobber existing output image?
(scale  =                 none) Image scaling
(statsec=                     ) Image section for computing statistics
(nlow   =                    1) 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)


produces


ERROR: No images to combine
  "pclip=pclip, grow=0)"
     line 47: ccdred$zerocombine.cl
     called as: `zerocombine ()'


but the files are clearly there with the correct keywords.

A d_trace produces


         ----- task cl - line 1 (CALL) -----
       1      77+6:     call            zerocombine
       1      83+3:     exec
        ----- exec script zerocombine (ccdred$zerocombine.cl) - line 1 -----
        ----- task zerocombine - line 33 (PUSHPARAM) -----
      33      89+5:     pushparam       input
List of zero level images to combine (zero*): 
      33      94+4:     assign          ims
      36      98+5:     pushparam       process
      36     103+6:     pushconst       yes
      36     109+3:     eq
      36     112+4:     biff            +49
      40     165+5:     call            combine
1: CALL combine
      40     170+4:     pushparam       ims
      40     174+4:     posargset       0
      40     178+5:     pushparam       output
      40     183+5:     absargset       output
      40     188+7:     pushconst       `'
      40     195+5:     absargset       plfile
      40     200+7:     pushconst       `'
      40     207+5:     absargset       sigma
      40     212+5:     pushparam       combine
      40     217+5:     absargset       combine
      41     222+5:     pushparam       reject
      41     227+5:     absargset       reject
      41     232+5:     pushparam       ccdtype
      41     237+5:     absargset       ccdtype
      41     242+6:     pushconst       no
      41     248+5:     absargset       subsets
      41     253+5:     pushparam       delete
      41     258+5:     absargset       delete
      42     263+5:     pushparam       clobber
      42     268+5:     absargset       clobber
      42     273+6:     pushconst       no
      42     279+5:     absargset       project
      42     284+8:     pushconst       `real'
      42     292+5:     absargset       outtype
      42     297+8:     pushconst       `none'
      42     305+5:     absargset       offsets
      43     310+8:     pushconst       `none'
      43     318+6:     absargset       masktype
      43     324+5:     pushparam       blank
      43     329+5:     absargset       blank
      43     334+5:     pushparam       scale
      43     339+5:     absargset       scale
      43     344+8:     pushconst       `none'
      43     352+5:     absargset       zero
      43     357+6:     pushconst       no
      43     363+5:     absargset       weight
      44     368+5:     pushparam       statsec
      44     373+5:     absargset       statsec
      44     378+6:     pushconst       INDEF
      44     384+6:     absargset       lthreshold
      44     390+6:     pushconst       INDEF
      44     396+6:     absargset       hthreshold
      44     402+5:     pushparam       nlow
      44     407+5:     absargset       nlow
      45     412+5:     pushparam       nhigh
      45     417+5:     absargset       nhigh
      45     422+5:     pushparam       nkeep
      45     427+5:     absargset       nkeep
      45     432+5:     pushparam       mclip
      45     437+5:     absargset       mclip
      45     442+5:     pushparam       lsigma
      45     447+5:     absargset       lsigma
      45     452+5:     pushparam       hsigma
      45     457+5:     absargset       hsigma
      46     462+5:     pushparam       rdnoise
      46     467+5:     absargset       rdnoise
      46     472+5:     pushparam       gain
      46     477+5:     absargset       gain
      46     482+5:     pushparam       snoise
      46     487+5:     absargset       snoise
      46     492+6:     pushconst       0.1
      46     498+6:     absargset       sigscale
      47     504+5:     pushparam       pclip
      47     509+5:     absargset       pclip
      47     514+6:     pushconst       0
      47     520+5:     absargset       grow
      47     525+3:     exec
        ----- exec external task combine - line 48 -----
            combine\ninput="zero*"\noutput="Zero"\nplfile=""\nsigma=""\n
            ccdtype="bias"\nsubsets=no\ndelete=no\nclobber=no\n
            combine="average"\nreject="minmax"\nproject=no\n
            outtype="real"\noffsets="none"\nmasktype="none"\n
            maskvalue=0.\nblank=0.\nscale="none"\nzero="none"\n
            weight="no"\nstatsec=""\nlthreshold=INDEF\nhthreshold=INDEF\n
            nlow=1\nnhigh=1\nnkeep=1\nmclip=yes\nlsigma=3.\nhsigma=3.\n
            rdnoise="rdnoise"\ngain="gain"\nsnoise="0."\nsigscale=0.1\n
            pclip=-0.5\ngrow=0\nmode="ql"\n$nargs=1\n
        --------------------------------
        ----- task combine - line 1115 (INSPECT) -----
    1115     531+6:     inspect         instrument
    1115     537+3:     end
        ----- task combine - line 1116 (CALL) -----
    1116     531+5:     call            error
1: CALL error
    1116     536+6:     pushconst       1
    1116     542+4:     posargset       0
    1116     546+12:    pushconst       `No images to combine'
    1116     558+4:     posargset       1
    1116     562+3:     exec
        ----- exec builtin error : line 1116 -----
        ----- disconnect noaobin$x_ccdred.e -----
ERROR: No images to combine
cl_error: abort=1  trace=1  flpr=1
cl_error: code=1 do_err=1 errtype=1/1 task='zerocombine'
  "pclip=pclip, grow=0)"
     line 47: ccdred$zerocombine.cl
     called as: `zerocombine ()'



In case it helps, here is my ccdproc too


PACKAGE = ccdred
   TASK = ccdproc

images  =               *.fits  List of CCD images to correct
(output =                     ) List of output CCD images
(ccdtype=                     ) CCD image type to correct
(max_cac=                    0) Maximum image caching memory (in Mbytes)
(noproc =                   no) List processing steps only?

(fixpix =                   no) Fix bad CCD lines and columns?
(oversca=                  yes) Apply overscan strip correction?
(trim   =                  yes) Trim the image?
(zerocor=                   no) Apply zero level correction?
(darkcor=                   no) Apply dark count correction?
(flatcor=                   no) Apply flat field correction?
(illumco=                   no) Apply illumination correction?
(fringec=                   no) Apply fringe correction?
(readcor=                   no) Convert zero level image to readout correction?
(scancor=                   no) Convert flat field image to scan correction?

(readaxi=                 line) Read out axis (column|line)
(fixfile=                     ) File describing the bad lines and columns
(biassec=                image) Overscan strip image section
(trimsec=                image) Trim data section
(zero   =                     ) Zero level calibration image
(dark   =                     ) Dark count calibration image
(flat   =                     ) Flat field images
(illum  =                     ) Illumination correction images
(fringe =                     ) Fringe correction images
(minrepl=                   1.) Minimum flat field value
(scantyp=            shortscan) Scan type (shortscan|longscan)
(nscan  =                    1) Number of short scan lines

(interac=                  yes) Fit overscan interactively?
(functio=             legendre) Fitting function
(order  =                    6) Number of polynomial terms or spline pieces
(sample =                    *) Sample points to fit
(naverag=                    1) Number of sample points to combine
(niterat=                    1) Number of rejection iterations
(low_rej=                   4.) Low sigma rejection factor
(high_re=                   4.) High sigma rejection factor
(grow   =                   0.) Rejection growing radius
(mode   =                   ql)


and imcombine


PACKAGE = immatch
   TASK = imcombine

input   =                       List of images to combine
output  =                       List of output images
(headers=                     ) List of header files (optional)
(bpmasks=                     ) List of bad pixel masks (optional)
(rejmask=                     ) List of rejection masks (optional)
(nrejmas=                     ) List of number rejected masks (optional)
(expmask=                     ) List of exposure masks (optional)
(sigmas =                     ) List of sigma images (optional)
(logfile=               STDOUT) Log file

(combine=              average) Type of combine operation
(reject =                 none) Type of rejection
(project=                   no) Project highest dimension of input images?
(outtype=                 real) Output image pixel datatype
(outlimi=                     ) Output limits (x1 x2 y1 y2 ...)
(offsets=                 none) Input image offsets
(masktyp=                 none) Mask type
(maskval=                    0) Mask value
(blank  =                   0.) Value if there are no pixels

(scale  =                 none) Image scaling
(zero   =                 none) Image zero point offset
(weight =                 none) Image weights
(statsec=                     ) Image section for computing statistics
(expname=                     ) Image header exposure time keyword

(lthresh=                INDEF) Lower threshold
(hthresh=                INDEF) Upper threshold
(nlow   =                    1) 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)
(sigscal=                  0.1) Tolerance for sigma clipping scaling corrections
(pclip  =                 -0.5) pclip: Percentile clipping parameter
(grow   =                   0.) Radius (pixels) for neighbor rejection
(mode   =                   ql)


The files are there... here's my directory


comp166.fits        dflat142.fits       obj204.fits
comp167.fits        dflat143.fits       obj205.fits
comp168.fits        dflat144.fits       obj206.fits
comp173.fits        dflat145.fits       obj207.fits
comp174.fits        dflat146.fits       obj208.fits
comp181.fits        dflat147.fits       obj209.fits
comp182.fits        dflat148.fits       obj210.fits
comp198.fits        dflat149.fits       obj211.fits
comp215.fits        dflat150.fits       obj212.fits
comp218.fits        dflat151.fits       obj213.fits
comp223.fits        logfile             obj214.fits
dflat112.fits       obj163.fits         obj216.fits
dflat113.fits       obj164.fits         obj217.fits
dflat114.fits       obj165.fits         obj219.fits
dflat115.fits       obj169.fits         obj220.fits
dflat116.fits       obj170.fits         obj221.fits
dflat117.fits       obj171.fits         obj222.fits
dflat118.fits       obj172.fits         zero152.fits
dflat119.fits       obj177.fits         zero153.fits
dflat120.fits       obj178.fits         zero154.fits
dflat121.fits       obj179.fits         zero155.fits
dflat122.fits       obj180.fits         zero156.fits
dflat123.fits       obj184.fits         zero157.fits
dflat124.fits       obj185.fits         zero158.fits
dflat125.fits       obj186.fits         zero159.fits
dflat126.fits       obj187.fits         zero160.fits
dflat127.fits       obj188.fits         zero161.fits
dflat128.fits       obj189.fits         zero162.fits
dflat129.fits       obj190.fits         zero224.fits
dflat130.fits       obj191.fits         zero225.fits
dflat131.fits       obj192.fits         zero226.fits
dflat132.fits       obj193.fits         zero227.fits
dflat133.fits       obj194.fits         zero228.fits
dflat134.fits       obj195.fits         zero229.fits
dflat135.fits       obj196.fits         zero230.fits
dflat136.fits       obj197.fits         zero231.fits
dflat137.fits       obj199.fits         zero232.fits
dflat138.fits       obj200.fits         zero233.fits
dflat139.fits       obj201.fits         zero234.fits
dflat140.fits       obj202.fits         
dflat141.fits       obj203.fits         


and their IMAGETYP values


comp166.fits    other
comp167.fits    other
comp168.fits    other
comp173.fits    other
comp174.fits    other
comp181.fits    other
comp182.fits    other
comp198.fits    other
comp215.fits    other
comp218.fits    other
comp223.fits    other
dflat112.fits   flat
dflat113.fits   flat
dflat114.fits   flat
dflat115.fits   flat
dflat116.fits   flat
dflat117.fits   flat
dflat118.fits   flat
dflat119.fits   flat
dflat120.fits   flat
dflat121.fits   flat
dflat122.fits   flat
dflat123.fits   flat
dflat124.fits   flat
dflat125.fits   flat
dflat126.fits   flat
dflat127.fits   flat
dflat128.fits   flat
dflat129.fits   flat
dflat130.fits   flat
dflat131.fits   flat
dflat132.fits   flat
dflat133.fits   flat
dflat134.fits   flat
dflat135.fits   flat
dflat136.fits   flat
dflat137.fits   flat
dflat138.fits   flat
dflat139.fits   flat
dflat140.fits   flat
dflat141.fits   flat
dflat142.fits   flat
dflat143.fits   flat
dflat144.fits   flat
dflat145.fits   flat
dflat146.fits   flat
dflat147.fits   flat
dflat148.fits   flat
dflat149.fits   flat
dflat150.fits   flat
dflat151.fits   flat
obj163.fits     object
obj164.fits     object
obj165.fits     object
obj169.fits     object
obj170.fits     object
obj171.fits     object
obj172.fits     object
obj177.fits     object
obj178.fits     object
obj179.fits     object
obj180.fits     object
obj184.fits     object
obj185.fits     object
obj186.fits     object
obj187.fits     object
obj188.fits     object
obj189.fits     object
obj190.fits     object
obj191.fits     object
obj192.fits     object
obj193.fits     object
obj194.fits     object
obj195.fits     object
obj196.fits     object
obj197.fits     object
obj199.fits     object
obj200.fits     object
obj201.fits     object
obj202.fits     object
obj203.fits     object
obj204.fits     object
obj205.fits     object
obj206.fits     object
obj207.fits     object
obj208.fits     object
obj209.fits     object
obj210.fits     object
obj211.fits     object
obj212.fits     object
obj213.fits     object
obj214.fits     object
obj216.fits     object
obj217.fits     object
obj219.fits     object
obj220.fits     object
obj221.fits     object
obj222.fits     object
zero152.fits    bias
zero153.fits    bias
zero154.fits    bias
zero155.fits    bias
zero156.fits    bias
zero157.fits    bias
zero158.fits    bias
zero159.fits    bias
zero160.fits    bias
zero161.fits    bias
zero162.fits    bias
zero224.fits    bias
zero225.fits    bias
zero226.fits    bias
zero227.fits    bias
zero228.fits    bias
zero229.fits    bias
zero230.fits    bias
zero231.fits    bias
zero232.fits    bias
zero233.fits    bias
zero234.fits    bias


At this point I'm checking whitespace and stuff in the keywords to see if makes any difference but so far none.

Jason

Francisco Valdes wrote on Oct 24, 2007

Hi Jason,

The value you specify for ccdtype is not the the literal value of the imagetyp keyword. There is a translation that takes place between what the ccdred package defines for image types and what is used in the headers. The ccdtype value for a bias is "zero". You can't change that. What you change is the instrument translation file to map what ccdred calls "zero" into whatever the data used to identify a bias. In you case you would need a translation file with something like


bias zero


in the instrument translation file. See "help instruments". Whenever you deal with the instrument translation mechanism it is useful to verify that ccdred understands your data by using ccdlist. If the zero type is understood correctly you would see [zero] as part of the output from ccdlist for your bias images.

I hope I have not misunderstood your situation.

Yours,
Frank Valdes

cristian wrote on Oct 24, 2007

Hello,
I am having problems when trying to use darkcombine and zerocombine commands.
This is what I get when using the darkcombine command:

ccdred> darkcombine
List of dark images to combine (dark_v_001.fit, dark_v_002.fit):
ERROR: No images to combine
"pclip=pclip, grow=0)"
line 47: ccdred$darkcombine.cl
called as: `darkcombine ()'

I have been reading at some other posts about similar problems, but none of the solutions proposed seems to work for me.
Any ideas?
Thanks,

Cristian

duck_85 wrote on Oct 24, 2007

Hello,
I am having a similar problem with both tasks.
I use zerocombine with the following par:
PACKAGE = ccdred
TASK = zerocombine

input = @bias.lst List of zero level images to combine
(output = bias_med.fit) Output zero level 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?
(clobber= no) Clobber existing output image?
(scale = none) 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 = 2.63) 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)

and i get this error:
Warning: Invalid image section (bias_b_001.fit[765,510][ushort][none]:bias)
Warning: Invalid image section (bias_b_002.fit[765,510][ushort][none]:bias)
Warning: Invalid image section (bias_b_003.fit[765,510][ushort][none]:bias)
Warning: Invalid image section (bias_b_004.fit[765,510][ushort][none]:bias)
Warning: Invalid image section (bias_b_005.fit[765,510][ushort][none]:bias)
Warning: Invalid image section (bias_b_006.fit[765,510][ushort][none]:bias)
Warning: Invalid image section (bias_b_007.fit[765,510][ushort][none]:bias)
Warning: Invalid image section (bias_b_008.fit[765,510][ushort][none]:bias)
Warning: Invalid image section (bias_b_009.fit[765,510][ushort][none]:bias)
Warning: Invalid image section (bias_b_010.fit[765,510][ushort][none]:bias)
ERROR on line 46: No images to combine
zerocombine (mode=h)

I use darkcombine with the following par:
PACKAGE = ccdred
TASK = darkcombine

input = @dark.lst List of dark images to combine
(output = darkmed.fit) Output dark image root name
(combine= median) Type of combine operation
(reject = minmax) Type of rejection
(ccdtype= ) 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 = 2.63) 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)

and I get this error:

ERROR on line 46: Cannot open image (Zero)
darkcombine (mode=h)

Thanks for any help,

Pat </div> --- **Francisco Valdes** wrote on Oct 24, 2007
Pat,

The second error with darkcombine comes from the fact that process=yes which means it first wants to process the images with ccdproc. The ccdproc parameters apply in this case. It appears to be looking for the bias image Zero. So the second error is probably a consequence of the first error.

I can't spot a problem with the zerocombine parameters. However, I would need to see the contents of the input list file. If the image specifications have image sections that might explain the error.

The best way to figure this out might be to use the d_trace toggle command to turn on the verbose output when zerocombine is run. This would give the exact command given to combine, which is the underlying task being used.

Yours,
Frank Valdes
--- **Francisco Valdes** wrote on Oct 24, 2007
Cristian,

I'm not sure if you really done the usual solution to the error you report. Try using the command


darkcombine ccdtype=""


Yours,
Frank Valdes
--- **cristian** wrote on Oct 24, 2007
Frank,

I have run the zerocombine task inputing the images one by one instead of directing the input to a txt file containing the list of images and it's worked. I don't get what the error was and i'd like to understand it, help please?

Thanks,

Cristian
--- **Francisco Valdes** wrote on Oct 24, 2007
Cristian,

Please be more specific by giving an example of what commands you use. Redirect and one-by-one are not clear to me.

Frank
--- **cristian** wrote on Oct 24, 2007
Sorry about that,

I meant the following parameters for zerocombine:

input = *.fit (all fit files in folder instead of a .txt list of images containing the names of the files i need combined)
output = bias_median.fit

everything else is the same as duck_85's. This way it works, but when i use a list like so:

input = @biaslist.txt
output = bias_median.fit

where the list includes:
bias_b_001.fit[765,510][ushort][none]:bias
bias_b_002.fit[765,510][ushort][none]:bias
bias_b_003.fit[765,510][ushort][none]:bias
bias_b_004.fit[765,510][ushort][none]:bias
bias_b_005.fit[765,510][ushort][none]:bias
bias_b_006.fit[765,510][ushort][none]:bias
bias_b_007.fit[765,510][ushort][none]:bias
bias_b_008.fit[765,510][ushort][none]:bias
bias_b_009.fit[765,510][ushort][none]:bias
bias_b_010.fit[765,510][ushort][none]:bias

it shows the error i posted before.

Sorry, thanks again,

Cristian </div> --- **Francisco Valdes** wrote on Oct 24, 2007
Aha,

Your list needs to be a list of files without the stuff about size, type, etc. You must have ccdlist to create the file. Instead you should use


cl> sections bais_b*fit > biaslist.txt
cl> type biaslist.txt
bias_b_001.fit
bias_b_002.fit
bias_b_003.fit
bias_b_004.fit
bias_b_005.fit
bias_b_006.fit
bias_b_007.fit
bias_b_008.fit
bias_b_009.fit
bias_b_010.fit


Frank
--- **jbkikwaya** wrote on Dec 07, 2016

I ran into the same problem and this is what I have done:

----------------------------------------------------------------------------------------

Load:

>imred

>ccdred

Change parameters to ccdproc

>epar ccdproc

PACKAGE = ccdred

TASK = ccdproc

images = List of CCD images to correct

(output = ) List of output CCD images

(ccdtype= zero) CCD image type to correct

(max_cac= 0) Maximum image caching memory (in Mbytes)

(noproc = no) List processing steps only?

(fixpix = no) Fix bad CCD lines and columns?

(oversca= no) Apply overscan strip correction?

(trim = no) Trim the image?

(zerocor= no) Apply zero level correction?

(darkcor= no) Apply dark count correction?

(flatcor= no) Apply flat field correction?

(illumco= no) Apply illumination correction?

(fringec= no) Apply fringe correction?

(readcor= no) Convert zero level image to readout correction?

(scancor= no) Convert flat field image to scan correction?

(readaxi= line) Read out axis (column|line)

(fixfile= ) File describing the bad lines and columns

(biassec= ) Overscan strip image section

(trimsec= ) Trim data section

(zero = ) Zero level calibration image

(dark = ) Dark count calibration image

(flat = ) Flat field images

(illum = ) Illumination correction images

(fringe = ) Fringe correction images

(minrepl= 1.) Minimum flat field value

(scantyp= shortscan) Scan type (shortscan|longscan)

(nscan = 1) Number of short scan lines

(interac= no) Fit overscan interactively?

(functio= legendre) Fitting function

(order = 1) Number of polynomial terms or spline pieces

(sample = *) Sample points to fit

(naverag= 1) Number of sample points to combine

(niterat= 1) Number of rejection iterations

(low_rej= 3.) Low sigma rejection factor

(high_re= 3.) High sigma rejection factor

(grow = 0.) Rejection growing radius

(mode = ql)

Change parameters to zerocombine

>epar zerocombine

PACKAGE = ccdred

TASK = zerocombine

input = *.fits List of zero level images to combine

(output = BIAS) Output zero level name

(combine= median) Type of combine operation

(reject = avsigclip) Type of rejection

(ccdtype= zero) CCD image type to combine

(process= no) Process images before combining?

(delete = no) Delete input images after combining?

(clobber= no) Clobber existing output image?

(scale = none) 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)

And then run zerocombine.

--- *Last post on Dec 07, 2016*