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Re: Time for Software
On Wed, 2 Aug 2000 13:38:06 -0400 , "Gutzwiller, Michael"
>I'll take a whack at the pipeline stages:
>Stage Input Output
>Camera Calibration Photons Dark Field, Flat Field
>Image Acquisition Photons FITS Image
>Star List Generation FITS Image, Star List (x,y)
> Dark Field,
> Flat Field
>Registration to Catalog Star List (x,y) Star List (ra,dec)
>Color Calibration Star List (x,y) Star List (ra,dec)
>Insert to database Star List (ra, dec) Observations database
I am working on a more complicated StarList Generation/Registration
to catalog process. In the above format it looks like:
Stage Input Output
Clean Image FITS Image, Clean Image
(Hot Pixel list?)
Preliminary Star List Clean Image, Star List (x,y)
Bright Star List
Other List (CR's etc)
Prelim Registration Star List (x,y), Prelim Astrometry,
Catalog Prelim Photometry
Select List for PSF Star List, Select list
Full List Star Lists, Full List (x,y)
PSF update Clean Image, PSF estimate
Fit Stars Clean Image, Full List, x,y,A
Registration Full List x,y, Final Astrometry,
Full List, RA,DEC,MAG
This degree of complexity allows one to look at stars which
would otherwise be below the detection threshold on some images,
thus eliminating one of the major shortcomings of TENXCAT.
There is nothing sacred about the order of events ... one
should probably work all the way through to final astrometry
and then go back and do the catalog merge stuff and produce
the final star list. The above precis is just the way it grew.
Even if you don't believe in fitted PSF's etc, the MK IV
processing should include the step of merging previously
seen objects into the finding list. This requires the
catalog matching step.
I am currently getting below 1 arc sec probable error for the
preliminary matching and around 0.3 arc sec for the final
match, using Tycho2.
Andrew Bennett, Avondale Vineyard, Nova Scotia, Canada.