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ccdinst noao.imred.ccdred


NAME · USAGE_ · PARAMETERS · DESCRIPTION · EXAMPLES · SEE_ALSO

NAME

ccdinstrument -- Setup and verify CCD instrument translation files

USAGE

ccdinstrument images

PARAMETERS

images
List of images to be verified or used to setup a CCD instrument translation file.
instrument = ")_.instrument"
CCD instrument translation file. The default is to use the translation file defined in the ccdred package parameters. Note that one would need write permission to update this file though the task has a write command to save any changes to a different file.
ssfile = ")_.ssfile"
Subset translation file. The default is to use the file defined in the ccdred package parameters.
edit = yes
Edit the instrument translation file? If "yes" an interactive mode is entered allowing translation parameters to be modified while if "no" the task is simply used to verify the translations noninteractively.
parameters = "basic"
Parameters to be displayed. The choices are "basic" to display only the most basic parameters (those needed for the simplest automation of ccdred tasks), "common" to display the common parameters used by the package (most of these are keywords to be written to the image rather than translated), and "all" to display all the parameters referenced by the package including the most obscure. For most uses the "basic" set is all that is important and the other options are included for completeness.

DESCRIPTION

The purpose of this task is to provide an interface to simplify setting up CCD instrument translation files and to verify the translations for a set of images. Before this task was written users who needed to set up translation files for new instruments and observatories had to directly create the files with an editor. Many people encountered difficulties and were prone to errors. Also there was no task that directly verified the translations though ccdlist provided some clues.

The ccdred package was designed to make intelligent use of information in image headers for determining things such as image calibration or object type and exposure times. While the package may be used without this capability it is much more convenient to be able to use information from the image. The package was also intended to be used with many different instruments, detectors, and observatories. The key to providing image header access across different observatories is the ability to translate the needs of the package to the appropriate keywords in the image header. This is done through a file called an "instrument translation file". For a complete description of this file and other instrument setup features of the package see ccdred.instruments .

The instrument translation file translates the parameter names used by the ccdred package into image specific parameters and also supplies default values for parameters. The translation proceeds as follows. When a package task needs a parameter for an image, for example "imagetyp", it looks in the instrument translation file. If the file is not found or none is specified then the image header keyword that is requested is assumed to have the same name. If an instrument translation file is defined then the requested parameter is translated to an image header keyword, provided a translation entry is given. If no translation is given the package name is used. For example the package parameter "imagetyp" might be translated to "data-typ" (the old NOAO CCD keyword). If the parameter is not found then the default value specified in the translation file, if present, is returned.

For recording parameter information in the header, such as processing flags, translation is also used. For example, if the flag specifying that the image has been corrected by a flat field is to be set then the package parameter name "flatcor" might be translated to "ff-flag". If no translation is given then the new image header parameter is entered as "flatcor".

The CCD image type requires a second level of translation also defined in the translation file. Once the image keyword which identifies the type of CCD image, for example a flat field or object, is translated to an imahe keyword the specific string value must be translated to one of the CCD image types used by the package. The translation works in the same way, the specific string found is translated to the ccdred type and returned to the task. This translation is tricky in that the exact string including all spaces and capitalizations must be correctly defined in the translation file. The ccdinstrument allows doing this automatically thus minimizing typing errors.

The basic display format of the task is a table of five columns giving the parameter name used by the package, the image keyword to which it is translated, the default value (if any), the value the task will receive for the current image after translation, and the actual keyword value in the image. A "?" is printed if a value cannot be determined. The idea of the task is to make sure that the value a ccdred task sees is the correct one and if not to modify the translation appropriately. In verify mode when the edit parameter is not set the translation table is simply printed for each input image.

In edit mode the user interactively gives commands at the ccdinstrument prompt to display or modify keywords. The modifications can then be written to the instrument file or saved in a private copy. The list of commands is shown below and may be printed using ? or help.

			CCDINSTRUMENT COMMANDS

?	    Print command summary
help	    Print command summary
imheader    Page image header
instrument  Print current instrument translation file
next	    Next image
newimage    Select a new image
quit	    Quit
read	    Read instrument translation file
show	    Show current translations
write	    Write instrument translation file

translate   Translate image string selected by the imagetyp
	    parameter to one of the CCDRED types given as an
	    argument or queried:
	    object, zero, dark, flat, comp, illum, fringe, other

The following are CCDRED parameters which may be translated. You are queried for the image keyword to use or it may be typed after the command. An optional default value (returned if the image does not contain the keyword) may be typed as the second argument of the command.

	BASIC PARAMETERS
imagetyp	Image type parameter (see also translate)
subset		Subset or filter parameter
exptime		Exposure time
darktime	Dark time (may be same as the exposure time)

The commands may be followed by values such as file names for some of the general commands or the keyword and default value for the parameters to be translated. Note this is the only way to specify a default value. If no arguments are given the user is prompted with the current value which may then be changed.

The set of parameters shown above are only those considered "basic". In order to avoid confusion the task can limit the set of parameters displayed. Without going into great detail, it is only the basic parameters which are generally required to have valid translations to allow the package to work well. However, for completeness, and if someone wants to go wild with translations, further parameters may be displayed and changed. The parameters displayed is controlled by the parameters keyword. The additional parameters not shown above are:

	USEFUL DEFAULT GEOMETRY PARAMETERS
biassec		Bias section (often has a default value)
trimsec		Trim section (often has a default value)

	COMMON PROCESSING FLAGS
fixpix		Bad pixel replacement flag
overscan	Overscan correction flag
trim		Trim flag
zerocor		Zero level correction flag
darkcor		Dark count correction flag
flatcor		Flat field correction flag

	RARELY TRANSLATED PARAMETERS
ccdsec		CCD section
datasec		Data section
fixfile		Bad pixel file

fringcor	Fringe correction flag
illumcor	Ilumination correction flag
readcor		One dimensional zero level read out correction
scancor		Scan mode correction flag
nscanrow	Number of scan rows

illumflt	Ilumination flat image
mkfringe	Fringe image
mkillum		Illumination image
skyflat		Sky flat image

ccdmean		Mean value
ccdmeant	Mean value compute time
fringscl	Fringe scale factor
ncombine	Number of images combined
date-obs	Date of observations
dec		Declination
ra		Right Ascension
title		Image title

EXAMPLES

1. To verify the translations for a set of images using the default translation file:

	cl> setinst "" review-
	cl> ccdinst dev$pix edit-
	Image: dev$pix
	Instrument file: 
	Subset file: subsets

	CCDRED    IMAGE     DEFAULT   CCDRED    IMAGE   
	PARAM     KEYWORD   VALUE     VALUE     VALUE   
	--------------------------------
	imagetyp  imagetyp            none      ?
	subset    subset                        ?
	exptime   exptime             ?         ?
	darktime  darktime            ?         ?

	cl> setinst "" site=kpno dir=ccddb$ review-
	cl> ccdinst dev$pix edit-
	Image: dev$pix

	Instrument file: ccddb$kpno/camera.dat
	Subset file: subsets

	CCDRED    IMAGE     DEFAULT   CCDRED    IMAGE   
	PARAM     KEYWORD   VALUE     VALUE     VALUE   
	--------------------------------
	imagetyp  data-typ            object    OBJECT (0)
	subset    f1pos               2         2
	exptime   otime               600       600
	darktime  ttime               600       600

2. Set up an instrument translation file from scratch.

	ccdinst ech???.imh instr=myccd edit+
	Warning: OPEN: File does not exist (myccd)
	Image: ech001.imh
	Instrument file: myccd
	Subset file: subsets
	
	CCDRED    IMAGE     DEFAULT   CCDRED    IMAGE   
	PARAM     KEYWORD   VALUE     VALUE     VALUE   
	------------------------------------------------------
	imagetyp  imagetyp            none      ?
	subset    subset                        ?
	exptime   exptime             ?         ?
	darktime  darktime            ?         ?
	
	ccdinstrument> imagetyp
	Image keyword for image type (imagetyp): ccdtype
	imagetyp  ccdtype             unknown   BIAS
	ccdinstrument> translate
	CCDRED image type for 'BIAS' (unknown): zero
	imagetyp  ccdtype             zero      BIAS
	ccdinstrument> subset
	Image keyword for subset parameter (subset): filters
	subset    filters             1         1 0
	ccdinstrument> exptime integ
	exptime   integ               0.        0.
	ccdinstrument> darktime integ
	darktime  integ               0.        0.
	ccdinstrument> show
	Image: ech001.imh
	Instrument file: myccd
	Subset file: subsets
	
	CCDRED    IMAGE     DEFAULT   CCDRED    IMAGE   
	PARAM     KEYWORD   VALUE     VALUE     VALUE   
	------------------------------------------------------
	imagetyp  ccdtype             zero      BIAS
	subset    filters             1         1 0
	exptime   integ               0.        0.
	darktime  integ               0.        0.
	
	ccdinstrument> next
	Image: ech002.imh
	Instrument file: myccd
	Subset file: subsets
	
	CCDRED    IMAGE     DEFAULT   CCDRED    IMAGE   
	PARAM     KEYWORD   VALUE     VALUE     VALUE   
	------------------------------------------------------
	imagetyp  ccdtype             unknown   PROJECTOR FLAT
	subset    filters             1         1 0
	exptime   integ               20.       20.
	darktime  integ               20.       20.
	
	ccdinstrument> trans
	CCDRED image type for 'PROJECTOR FLAT' (unknown): flat
	imagetyp  ccdtype             flat      PROJECTOR FLAT
	ccdinstrument> next
	Image: ech003.imh
	Instrument file: myccd
	Subset file: subsets
	
	CCDRED    IMAGE     DEFAULT   CCDRED    IMAGE   
	PARAM     KEYWORD   VALUE     VALUE     VALUE   
	------------------------------------------------------
	imagetyp  ccdtype             unknown   COMPARISON
	subset    filters             1         1 0
	exptime   integ               300       300
	darktime  integ               300       300
	
	ccdinstrument> translate comp
	imagetyp  ccdtype             comp      COMPARISON
	ccdinstrument> next
	Image: ech004.imh
	Instrument file: myccd
	Subset file: subsets
	
	CCDRED    IMAGE     DEFAULT   CCDRED    IMAGE   
	PARAM     KEYWORD   VALUE     VALUE     VALUE   
	------------------------------------------------------
	imagetyp  ccdtype             unknown   OBJECT
	subset    filters             1         1 0
	exptime   integ               3600      3600
	darktime  integ               3600      3600
	
	ccdinstrument> translate object
	imagetyp  ccdtype             object    OBJECT
	ccdinstrument> inst
	imagetyp                      ccdtype 
	BIAS                          zero    
	subset                        filters 
	exptime                       integ   
	darktime                      integ   
	'PROJECTOR FLAT'              flat    
	COMPARISON                    comp    
	OBJECT                        object  

	ccdinstrument> next
	Update instrument file myccd (yes)? 

3. Set default geometry parameters. Note that to set a default the arguments must be on the command line.

	cc> ccdinst ech001 instr=myccd param=common edit+
	Image: ech001
	Instrument file: myccd
	Subset file: subsets
	
	CCDRED    IMAGE     DEFAULT   CCDRED    IMAGE   
	PARAM     KEYWORD   VALUE     VALUE     VALUE   
	------------------------------------------------------
	imagetyp  ccdtype             zero      BIAS
	subset    filters             1         1 0
	exptime   integ               0.        0.
	darktime  integ               0.        0.
	
	biassec   biassec             ?         ?
	trimsec   trimsec             ?         ?
	
	fixpix    fixpix              no        ?
	overscan  overscan            no        ?
	trim      trim                no        ?
	zerocor   zerocor             no        ?
	darkcor   darkcor             no        ?
	flatcor   flatcor             no        ?
	
	ccdinstrument> biassec biassec [803:830,*]
	biassec   biassec   [803:830,*]  [803:830,*]  ?
	ccdinstrument> trimsec trimsec [2:798,2:798]
	trimsec   trimsec   [2:798,2:798]  [2:798,2:798]  ?
	ccdinstrument> instr
	trimsec                       trimsec  [2:798,2:798]
	biassec                       biassec  [803:830,*]
	imagetyp                      ccdtype 
	BIAS                          zero    
	subset                        filters 
	exptime                       integ   
	darktime                      integ   
	'PROJECTOR FLAT'              flat    
	COMPARISON                    comp    
	OBJECT                        object  
	
	ccdinstrument> q
	Update instrument file myccd (yes)? 

SEE ALSO

instruments, setinstrument


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