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The calibration software takes as input the raw WF/PC-1 data file pairs (Table 44.1 on page 44-2) d0h/d0d, q0h/q0d, x0h/x0d, q1h/q1d and any necessary calibration reference images or tables. The software determines which calibration steps to perform by looking at the values of the calibration switches (e.g., MASKCORR, BIASCORR, etc.) in the header of the raw data (.d0h) file. Likewise, it selects the reference files to use in the calibration of the data by examining the reference file keywords (e.g., MASKFILE, BIASFILE, BIASDFILE, etc.). The appropriate values of the calibration switches and reference file keywords depend on the instrumental configuration used, the date when the observations were taken, and any special pre-specified constraints. They were initially set in the headers of the raw data file in the RSDP pipeline during generic conversion; for recalibrating, they can be redefined (using hedit for example) and calwfp run on the raw files.
To determine what calibration steps the pipeline applied to the data and which calibration reference files were used to calibrate the data, examine the values of the calibration switches in the header of the raw (or calibrated) data. Prior to calibration, the calibration switches will have the value YES, NO, or PERFORM. After calibration, the switches for completed steps will have been assigned the value COMPLETE in the header keywords of the calibrated data file.
There are history records at the bottom of the header file of the calibrated data (as
well as the calibration reference file headers). These history records sometimes
contain important information regarding the reference files used to calibrate the
data in the pipeline.
The flow chart below summarizes the sequence of calibration steps performed by calwfp, including the input calibration reference files and tables, and the output data files from each step. The purpose of each calibration step is briefly described in the accompanying table; a more detailed explanation is provided in the following section.Figure 45.2: Pipeline Processing by -calwfp
Calibration Steps and -Reference Files Used for WF/PC-1 -Pipeline
Processing
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