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daoedit noao.digiphot.daophot



daoedit -- edit the daophot package parameters interactively


daoedit image


icommands = ""
The image display cursor or image cursor commands file.
gcommands = ""
The graphics cursor or graphics cursor commands file.
cache = ")_.cache"
Cache the image pixels in memory. Cache may be set to the value of the apphot package parameter (the default), "yes", or "no". By default cacheing is disabled.
graphics = ")"
The standard graphics device.
display = ")_.display"
The standard display device.


DAOEDIT is a general purpose tool for interactively examining and editing the DAOPHOT algorithm parameters located in the parameter sets DATAPARS, FINDPARS, CENTERPARS, FITSKYPARS, PHOTPARS, and DAOPARS. These five parameter sets can be be listed, edited, and/or unlearned as a group from within DAOEDIT using the IRAF LPAR, EPAR and UNLEARN utilities. Any parameter in each of these five parameter sets can be examined or edited individual using a simple ommand. Parameters which are defined in terms of radial distance from the center of a star or in terms of image counts can be examined and edited interactively using radial profile plots and the graphics cursor.

If cache is yes and the host machine physical memory and working set size are large enough, the input image pixels are cached in memory. If cacheing is enabled the first data measurement will appear to take a long time as the entire image must be read in before the measurement is actually made. All subsequent measurements will be very fast because DAOEDIT is accessing memory not disk. The point of cacheing is to speed up random image access by making the internal image i/o buffers the same size as the image itself. At present there is no point in enabling cacheing for images that are less than or equal to 524288 bytes, i.e. the size of the test image dev$ypix, as the default image i/o buffer is exactly that size. However if the size of dev$ypix is doubled by converting it to a real image with the chpixtype task then the effect of cacheing in interactive is can be quite noticeable if measurements of objects in the top and bottom halfs of the image are alternated.


		      Interactive Keystroke Commands

?	Print help
:	Colon commands
a	Estimate center, sky, skysigma, fwhmpsf and magnitude of a star
r	Plot the radial profile of a star and its integral
i	Set selected parameters interactively using a radial profile plot
g	Toggle between image and graphics cursor
x	Toggle the radial profile plot between pixel and scale units
y	Toggle the radial profile plot between counts and normal units
q	Quit task

		      Colon Commands

:lparam/eparam/unlearn	pset	List/edit/unlearn the named pset
:parameter	        [value]	List or set an individual pset parameter


datapars	The data dependent parameters
findpars	The daofind task object detection parameters
centerpars	The phot task centering algorithm parameters
fitskypars	The phot task sky fitting algorithm parameters
photpars	The phot task photometry algroithm parameters
daopars		The psf fitting algorithm parameters

The following commands are available from within the interactive setup

	    Interactive Daoedit Setup Menu

?	Print help
spbar	Mark/verify critical parameters (f, s, a, d, r, w, b)
q	Quit

f	Mark/verify the fwhm of the psf on the radial profile plot
s	Mark/verify the sky sigma on the radial profile plot
l	Mark/verify the minimum good data value on the radial profile plot
u	Mark/verify the maximum good data value on the radial profile plot

c	Mark/verify the centering box half-width on the radial profile plot
n	Mark/verify the cleaning radius on the radial profile plot
p	Mark/verify the clipping radius on the radial profile plot

a	Mark/verify the inner sky annulus radius on the radial profile plot
d	Mark/verify the width of the sky annulus on the radial profile plot
g	Mark/verify the sky region growing radius on the radial profile plot

r	Mark/verify the photometry aperture(s) on the radial profile plot
w	Mark/verify the psf function radius on the radial profile plot
b	Mark/verify the psf fitting radius on the radial profile plot


1. Setup the daophot package parameters interactively for the image m92. This example assumes that the parameters are all initially at their default values.

	da> display dev$ypix 1
	da> daoedit dev$ypix

	    ... type :e datapars to edit the data dependent parameters
	    ...	leave scale at 1.0 and datamin at INDEF but set the
	        datamax, readnoise, epadu, exposure, airmass, filter,
		and obstime parameters to appropriate values
	    ... type :l datapars to check the results of the editing

	    ... type :e findpars to check the object detection parameters
	    ... change the findpars threshold parameter from 4.0 to 5.0
		using the command :threshold 5.0

	    ... type i to enter the interactive setup menu
		set the fwhmpsf, sigma, inner radius of the sky annulus,
		width of the sky annulus, photometry aperture(s), psf
		radius, and fitting radius using the radial profile
		plot and graphics cursor

	    ... select a bright non-saturated star and check that its
		radial profile is normal using the r keystroke command
	    ... note the value of the standard deviation of the sky
	        background written in the plot header
	    ... set the datapars sigma parameter to this value using
		the command :sigma <value>

	    ... check the data definition, centering, sky fitting,
	        photometry, and psf fitting parameters with the commands
		:l datapars, :l centerpars, :l fitskypars, :l photpars,
		and :l daopars





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