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Instructions for Using On-the-Fly Reprocessing (OTFR)

  • OTFR is currently available for WFPC2, NICMOS, and ACS data. In fact, the only source of calibrated data for these instruments is OTFR.
  • Both the Web interface and Starview provide access to OTFR.
    • On the Web interface, you will find the Science Files Requested box on the HST Retrieval Configuration Options screen. The use may choose the "Calibrated" and/or "Uncalibrated options. Either set of data will be produced by OTFR and you will be shipped only the files you asked for.
    • On Starview, make the request as you normally would. On the Retrieval Request - File Options screen, you will find a check box for Calibrated data.

      More detailed information about each dataset is found by going to the HST Instrument Searches screen from the Starview Search Menu. From there, select on the OTFR menu option for the appropriate instrument search. The OTFR screen contains some fields that are useful for determining if your data need reprocessing. The date of last software change is the most recent date of installation of new calibration software which will likely have a significant impact on the results of calibration. The date of last action update is the date of the last change of parameters for the dataset that could affect the results of calibration. You can use this information to determine whether there is any benefit in re-requesting a dataset from OTFR. If the dataset you have already obtained from OTFR was processed after both dates, then there is likely to be no significant advantage in requesting the dataset again.

    • If you have requested only calibrated data and the chosen dataset is not supposed to be calibrated, then no files are returned with a normal complete status. If the data was supposed to be calibrated but fails to process, operations staff will work to diagnose the problem if possible and talk with you about the problem. If you have checked uncalibrated data, you will receive the uncalibrated data.