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autophot

Autophot uses IRAF's digiphot daophot routines, it automates the procedure a bit.

Version : 30Sep2001
Author(s) : http://www.vuw.ac.nz/~reid/index.html
License : Free
Website : http://www.vuw.ac.nz/~reid/software.html

Disk space required for installation is 46.46 Mb

After the package is installed it can be accessed using the command


		/opt/lfa/startautophot

A shortcut will be installed in the KDE/GNOME desktop menu system,
as an entry in the Astronomy submenu

The following printable documents will be installed :

Summary

The current version of the software suite is autophot_30Sept2001 which has fixed many bugs. Some of the new features are

An experimental difference imaging program is being worked on in the convolve/ subdirectory. This should be finished in a few months.
The autophot programs themselves have been modified to estimate the sky background using either an annulus which scales with the image FWHM (which was done in older versions
of the software), and an annulus with fixed inner and outer radii (new). Using a fixed sky annulus gives much better results when using DAOphot II/Allstar when seeing conditions
are poor. Unfortunately the manual included in the distribution does not yet described the fixed annulus flags (I'll get on to it, I promise).
An improved point-source microlensing fitter, as well a new finite-source microlensing fitter are in the fitter2/ subdirectory.
StarBase will report the locations of stars within a rectangular region of the CCD. Useful for finding other objects near a star of interest. The number of observations for each object is
also reported. This is useful as DoPHOT tends to introduce false objects so finding the location of the true object is essential if its lightcurve is to be recovered.
StarBase will estimate and store the mean magnitudes of objects in a starfield, after rejecting outliers. Useful for constructing catalogues.
StarBase will construct catalogues using mean object magnitudes which can be used as fixed-position warmstart templates for DoPHOT. Databases made from DAOphot II
photometry produce excellent catalogues which (speedy) DoPHOT can then use.
When the magnitude zeropoint for each frame is estimated the uncertainty in the zeropoint is also estimated (at least for the constant term). This uncertainty can be added in
quadrature with the fitting error produced by DAOphot/DoPHOT when extracting lightcurves from the database. This produces much more realistic estimates of the uncertainty in the
lightcurve, and can lead to more realistic chi-square values of microlensing model fits.
Starbase can remove starfields from the database. Unfortunately, removal of individual exposures is broken (this is first on my to-do list).




Screenshots

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