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Running REDUCE/CCD
The command REDUCE/CCD can process one or more science frames
automatically provided that:
- the association table correctly describes the associations between
the science frames and the calibration frames;
- the CCD reduction table or the SC_... keywords contains the
correct names of the master calibration frames;
- the keywords for creating the calibration frames are correctly
set.
The standard default calibration procedure involves the following
processing: overscan subtraction, trimming, bias and dark subtraction,
and flat fielding. The keywords to be set for controlling these options
are listed in Table 3.3.
Below we describe how the command will try to correct your data.
REDUCE/CCD will first identify the Association Table. From
this table it gets the names of the input science frames. Next, it
will try to find the master calibration frames listed in the table,
and will create these if they do not exist yet.
After having collected all required calibration data the input
frame is checked for its exposure type. Obviously, a dark frame
should not be flat fielded and hence the processing options for
the dark exposures should be set differently than for the science
frames. After having determined the processing options the actual
processing starts.
Next: Overscan correction and trimming
Up: Processing the Data
Previous: How the Data is
Petra Nass
1999-06-15