D2ICAL
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Last Updated Jan 2001
Copyright © 2001 The Association of Universities for Research in Astronomy, Inc. All Rights Reserved.
Purpose :
Determine D-I curve and PSF function for plate and compute stellar magnitude by fitting PSF.Procedure :
This routine is based on the published algorithm by the APM group where the areal profile is used to determine a PSF and D-I curve. An initial estimate of the PSF is made by taking the lowest threshold data (where density is approx. linear with intensity) for stars of all brightnesses. NEED MORE EXPLANATION HERE OF ITERATIVE LOOP. The main improvement in this implementation is the addition of a fit to the photometric sequence stars in the iteration loop. This assures that the solution converges and has slope of approximately one.Calling Sequence :
- D2ICAL oopfile
- [/qualifiers TBD]
Availability :
- GSSS AXP - in development
- GSSS VAX - no
- PIXELS - no
History/Author :
- Original Implementation - Brian McLean