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Space Telescope Imaging Spectrograph Instrument Handbook for Cycle 22 > Chapter 15: Overview of Pipeline Calibration > 15.2 How Phase II Parameter Choices Affect Calibration

15.2
 
Calibrated through flat fielding only; no 2-D rectification, cosmic ray rejection (if applicable), flux calibration, or 1-D extraction.
MODE=ACQ or ACQ/PEAK
Data events are tabulated in rootname_tag.fits file with one binary table extension for each buffer read (determined by exposure time and BUFFER-TIME parameters). All raw data events are gathered into a single image, rootname_raw.fits, which is then passed through the normal calibration steps.
CCD only
CR-SPLIT > 1
or
The number of imsets in the raw file equals CR-SPLIT or Number_of_Iterations. Raw file imsets are cosmic ray rejected and summed before the bias, dark, and flat-fielding corrections are made, producing a rootname_crj.fits file. The individual imsets are also flagged for cosmic rays and processed without summing to produce a rootname_flt.fits file.
MAMA only
Number_of_Iterations > 1
The raw file contains Number_of_Iterations imsets, as do the flat-fielded and 2-D rectified files; the 1-D extracted files contain Number_of_Iterations tables. Repeat exposure imsets are summed after flat-fielding and 2-D rectification producing files rootname_sfl.fits and rootname_x2d.fits respectively (this is also true for imaging data). Note that for the MAMA detectors, 1-D spectral extraction data are not summed even when there are repeat exposures.
Separate PATTERN step exposures are not associated with each other. Each PATTERN step exposure is processed through calibration independently.
No 1-D extraction or 2-D rectification of spectral data will be done, because the associated wavelengths would be incorrect and therefore misleading.
An internal STIS CCD flat-field lamp exposure useful in post-pipeline processing to correct for fringing above ~7000 with gratings G750L and G750M.

Space Telescope Imaging Spectrograph Instrument Handbook for Cycle 22 > Chapter 15: Overview of Pipeline Calibration > 15.2 How Phase II Parameter Choices Affect Calibration

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