From: Wei Zheng <zheng@adcam.pha.jhu.edu ([email]zheng@adcam.pha.jhu.edu[/email])>
Date: Oct 18, 2005 7:31 AM
Subject: ccdproc
To: iraf@noao.edu ([email]iraf@noao.edu[/email])
Hello,
I am reprocessing a Gemini-NIRI image taken in 2003, using "ccdproc". The
process went OK in 2004, but for some reason I could not repeat it. The error
message is: "ERROR: Image header parameter not found (exptime)"
I compare with the header of a processed image, there is no "exptime" item
there, so the error message must indicate something else. I note that the image
type is "int" instead of "real".
Here is the header line of an image I processed before.
s570[1000,1000][real]: CL0016.5+1654
No bad pixels, min=-10464560., max=3157267.
Line storage mode, physdim [1000,1000], length of user area 2673 s.u.
Created Mon 11:39:17 17-Oct-2005, Last modified Sat 20:19:28 03-Jan-2004
Pixel file "s570.fits" [ok]
EXTEND  =                    F / File may contain extensions
DATAMIN =           -10464560. / Minimum data value
DATAMAX =             3157267. / Maximum data value
ORIGIN  = 'NOAO-IRAF FITS Image Kernel December 2001' / FITS file originator
DATE    = '2004-01-04T00:53:42'
IRAF-TLM= '20:19:28 (03/01/2004)'
OBJECT  = 'CL0016.5+1654'      / Name of the object observed
CTYPE1  = 'RA---TAN'           / the coordinate type for the first axis
CRPIX1  =     359.732700699404 / x-coordinate of reference pixel
CRVAL1  =     4.62930149949359 / first axis value at ref pixel
CTYPE2  = 'DEC--TAN'           / the coordinate type for the second axis
CRPIX2  =     491.579814040775 / y-coordinate of reference pixel
CRVAL2  =     16.4355526071162 / second axis value at ref pixel
CD1_1   = -1.20157584029395E-05 / partial of first axis coord w.r.t. x
CD1_2   = 3.02983983564036E-05 / partial of first axis coord w.r.t. y
CD2_1   = 3.04365236703421E-05 / partial of second axis coord w.r.t. x
CD2_2   = 1.15467525865043E-05 / partial of second axis coord w.r.t. y
MJD_OBS =     52874.5958717723 / Mean Julian day of observation
FRAME   = 'FK5     '           / Target coordinate system
DROINUM =                    0 / Which Region of Interest
LOWROW  =                    0 / Start row of region of interest
LOWCOL  =                    0 / Start col of region of interest
HIROW   =                 1023 / End row of region of interest
HICOL   =                 1023 / End col of region of interest
FRMNAME = 'N20030823S0570:0'   / Frame name
FRAMEID = '0       '           / Frame ID
DATATYP = '        '           / Data type
OBJMASK = 's570.ssm.pl'
SKYMED  =          8.153720E-5
WCSDIM  =                    2
LTM1_1  =                   1.
LTM2_2  =                   1.
WAT0_001= 'system=image'
WAT1_001= 'wtype=tan axtype=ra'
WAT2_001= 'wtype=tan axtype=dec'
TRIM    = 'Jan  3 19:53 Trim data section is [13:1012,13:1012]'
ZEROCOR = 'Jan  3 19:53 Zero level correction image is Zero'
FLATCOR = 'Jan  3 19:53 Flat field image is Flath with scale=1.000019'
CCDSEC  = '[13:1012,13:1012]'
BIASSEC = '[1:1000,1:1000]'
LTV1    =                 -12.
LTV2    =                 -12.
CCDMEAN =             12209.29
CCDMEANT=            757626822
CCDPROC = 'Jan  3 19:53 CCD processing done'
[b:82e9a169d0]From: [/b:82e9a169d0]Frank Valdes <valdes@noao.edu ([email]valdes@noao.edu[/email])>
[b:82e9a169d0]Date: [/b:82e9a169d0]November 3, 2005 3:03:55 PM MST
[b:82e9a169d0]To: [/b:82e9a169d0]Wei Zheng <zheng@adcam.pha.jhu.edu ([email]zheng@adcam.pha.jhu.edu[/email])>
[b:82e9a169d0]Subject: [/b:82e9a169d0][b:82e9a169d0]Re: ccdproc[/b:82e9a169d0]
Hello Wei,
I'm sorry for the delay in replying.
I would need to see the command you type and a listing showing the hidden parameters (e.g. lpar ccdproc ccdred).  Only some operations need to have an exposure time.  So maybe you added a processing step you did not use before.  The way CCDPROC determines the keyword for the exposure time is through an instrument translation file specified in the package parameters; e.g. in ccdred.  If no file is specified or it doesn't translate the keyword it uses the default keyword EXPTIME.  The problem will have nothing to do with whether the image pixels are integer or real.
Yours,
Frank Valdes
[I don't seem to have received a reply.  FV]