pstselect image photfile pstfile maxnpsf
image
The list of images containing the candidate psf stars.
photfile
The list of input files containing the
photometry for the candidate psf stars. If photfile is
"default", "dir$default" or a directory specification, PSTSELECT
looks for a file called image.mag.? where ? is the highest
existing version number. Otherwise photfile must specify one
photometry file for each input image in image. Photfile is
normally the output of the PHOT task but may also be the output
of the PSF, PEAK, NSTAR and ALLSTAR tasks. Photfile may be a
text file or an STSDAS database file.
pstfile
The list of output files containing the candidate psf stars.
If pstfile is "default", "dir$default", or
a directory specification then PSTSELECT writes a file called
image.pst.? where ? is the next available version number.
Otherwise pstfile must specify one output file for every
input image. Pstfile inherits its file type, either APPHOT/DAOPHOT
text or STSDAS binary table format, from photfile.
maxnpsf = 25
The maximum number of candidate psf stars to be selected.
plotfile =
The name of the output file containing mesh, contour, or
profile plots of the selected PSF stars. If plotfile is null
("") no plot file is created, otherwise a mesh, contour, or
profile plot is written to this file for each PSF star
selected. Plotfile is opened in append mode and can become very
large.
datapars =
The name of the text file containing the data dependent
parameters. If datapars is null ("") then the default
parameter set in the user's uparm directory is used. The parameter
scale is located here.
daopars =
The name of the text file containing the daophot fitting
parameters. If daopars is null ("") then the default parameter
set in the user's uparm directory is used. The parameters psfrad
and fitrad are located here.
interactive = no
Select the psf stars interactively? If interactive = yes and icommands is
null (""), PSTSELECT will read in the star list photfile, sort the
stars by magnitude and then wait for commands from the user. If
interactive=no and icommands="", PSTSELECT selects candidate PSF
stars from photfile without intervention by the user. If icommands
is not "", then interactive is automatically set to "no", and
commands are read from the image cursor command file.
plottype = mesh
The default type of plot displayed when selecting PSF stars.
The choices are "mesh", "contour", or "radial".
verbose = )_.verbose
Print messages about the progress of the task?
verify = )_.verify
Verify the critical task parameters?
update = )_.update
Update the critical task parameters if verify is "yes"?
graphics = ")_.graphics" The default graphics device. Graphics can be set to the default daophot package parameter value, "yes", or "no".
display = )_.display
The default image display device. Display can be set to the
default daophot package parameter value, "yes", or "no".
icommands =
The image display cursor.
gcommands =
The graphics cursor.
PSTSELECT reads the input photometry file photfile, extracts the ID, XCENTER, YCENTER, MAG, and MSKY fields from photfile for a list of up to maxnpsf psf stars, and writes them to pstfile. Pstfile inherits its file format, whether APPHOT/DAOPHOT text or STSDAS binary table format, from photfile.
PSTSELECT reads in the stars in photfile, sorts them in order of increasing magnitude, rejecting any stars that have INDEF valued magnitudes, or which lie less than fitrad / scale pixels from the edge of the image image. From this list the brightest maxnpsf stars which have no brighter stars within a distance of (psfrad + fitrad) / scale + 1 pixels are selected as candidate psf stars. Psfrad and fitrad are the psf radius and fitting radius parameters respectively and are located in the DAOPARS task. Scale is the image scale parameter and is located in the DATAPARS task. Plots, either mesh, contour or radial profile depending on the value of plottype of the selected stars may be saved in the file plotfile.
If interactive = "no", PSTSELECT reads the star list in photfile, selects the candidate psf stars, and writes the results to pstfile without input from the user. If interactive = "yes", PSTSELECT reads in the star list and waits for instruction from the user. At this point the user can step through the stars selected by PSTSELECT, examining their surface, countour, or radial profile plots for blemishes, neighbours etc, accepting good candidates and rejecting poor ones, or use the cursor and/or id number to select stars until a maximum of maxnpsf stars is reached. At any point a previously selected psf star can be accepted or deleted.
The following cursor commands are available once the image cursor
has been activated.
Keystroke Commands
? Print help
p Print photometry for star nearest the cursor
l List the current psf stars
n Select the next good candidate psf star from the list
a Add star nearest cursor to psf star list
d Delete psf star nearest cursor from psf star list
q Quit task
Colon Commands
:p [n] Print photometry for star n
:a [n] Add star n to psf star list
:d [n] Delete star n from psf star list
The following cursor commands are available once a star has been selected
and the graphics cursor has been activated.
Interactive Graphics Keystroke Commands
? Print help
p Print the photometry for this star
t Print the plot parameters and data minimum and maximum
a Accept star and proceed
d Reject star and select another with image cursor
m Plot the default mesh plot for this star
n Increase vertical angle by 15 degrees (mesh plot only)
s Decrease vertical angle by 15 degrees (mesh plot only)
w Decrease horizontal angle by 15 degrees (mesh plot only)
e Increase horizontal angle by 15 degrees (mesh plot only)
c Plot the default contour plot for this star
r Plot the radial profile for this star
Colon Graphics Commands
:m [val] [val] Set the mesh plot vertical and horizontal viewing angles
:v [val] Set the mesh plot vertical viewing angle
:h [val] Set the mesh plot horizontal viewing angle
:c [val] [val] Set the contour plot floor and ceiling levels
:l [value] Set the contour plot floor level
:u [value] Set the contour plot ceiling level
If verbose = "yes" a single line is written to the terminal for each star added to the candidate psf star list. Full output is written to the file pstfile. At the beginning of the file is a header listing the current values of all the important parameters. For each star included in the candidate psf star list the following quantities are written.
id xcenter ycenter mag msky
Id, xcenter, ycenter, mag, and msky are the id, x and y coordinates, magnitudes and sky values for the candidate psf stars as listed in photfile.
1. Select up to 10 psf stars from the PHOT task output non-interactively. Save surface plots of the selected stars in the file "plots".
da> pstselect m92 default default 10 plotfile=plots
2. Repeat example the first example running pstselect in interactive mode but do not save the plots.
da> pstselect m92 default default 10 interactive+
... verify the critical parameters as instructed
... when the image cursor appears type the n keystroke
command to select the first suitable candidate psf
star, examine its surface plot, and type a or d to
accept or reject the candidate star
... repeat the previous command until 10 psf stars have
been selected, the end of the star list is reached,
or a sufficient number of stars but fewer than maxnpsf
have been selected
... if fewer than maxnpsf stars are found automatically
additional psf stars can be added to the list with the a
keystroke command
... type q to quit