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Removing Irrelevant Columns

With the ESO CCD systems currently in use, some columns or/and rows are added in electronically and contain no valid data. The command:

EXTRACT/CCD extr_coords [catalog]
will remove these columns from all frames in the referenced catalog. The default is the general catalog. This function will slightly speed up subsequent operations and will avoid possible problems with strange pixel values sometimes found in these columns.

Petra Nass