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Instructions for Processing TASS Data
What you need:
-
A PC running Windows 95/98 or NT
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A large amount of disk space
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One nights run is about 240Mbytes. You should have about 350Mbytes free
before you start
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Software from The TASS Group Archive (Software can be downloaded
for free).
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A CD-ROM to read the JHU/APL TASS data
The software consists of 5 Windows applications programs:
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Dark - which takes a dark image, creates a corresponding dark
vector by finding the median value in each column, and allows you to save
the dark vector as a FITs file which will be used by other analysis programs.
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Flat - which takes a raw image file, subtracts a dark vector, and
creates a flat vector by finding the median ratios of each column, and
allows you to save the flatvector as a FITs file which will be used by
other analysis programs.
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Star - which takes a raw image, subtracts a dark vector, divides
by a flat vector, and creates the corrected image. The corrected
image may then be saved in FITS format. Star will also produce star
lists from the corrected image. The new version of star also requires
either the SAO catalog subset (147 Kb, Mar 16, 1997), the Guide Star Catalog
subset (840 Kb, Mar 17, 1997), or the recommended) Tycho catalog subset
(1139 Kb, Sep 7, 1997) to solve for exact RA and Declination. The
catalogs may now be located in any directory on your machine.
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StarPost - which takes a set of star lists generated by the star
program an sorts them into two separate directories based on pass/fail
criteria.
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FlatComp - which works in two passes. In the first pass it calculates
correction vectors for magnitudes based on a set of star lists and the
Good Tycho Catalog subset (311 Kb, September 15, 1998). The Good
Tycho catalog stars are those which have good photometry, are not
too close to other Tycho stars, and fit the color range for Arne Hendon's
color transformation. The second pass uses a set of correction vectors
previously created and modifies the magnitudes of all the stars in the
lists.
A short introduction to TASS
Data Analysis for the Novice.
For more information, contact: Dr.
Nicholas Beser
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