Calibration Products
and Tools

Below are listed the most recent releases of FOS calibration products.

POA_CALFOS pipeline final version (1.2.1) available as part of ST-POA package release.:

POA_CALFOS replaces CALFOS as the standard IRAF STSDAS FOS calibration package offering an improved correction to the zero point offsets, dispersion relations and dark correction and new flatfields files appropriate for use with the POA_CALFOS pipeline. Version 1.2 was the final major release, v1.2.1 supplements this with some minor patches and updates.

FOS Reference Files and Tables Guides:

(30 Jan 1998) Listings based upon FOS Calibration Closeout. AIS reference files and tables and SINGLE aperture post-COSTAR flatfield reference files are provided.

FOS/BL Wavelength Quick-FIX cl script available.

(30 September 1998) FOS/BL wavelength zero-points shifted systematically from launch through de-commissioning by a total peak-to-peak amount of approximately 7 quarter-stepped pixels (1.75 diodes). A quick-fix correction algorithm is provided to allow post-calfos correction of the wavelengths in FOS/BL wavelength data files (.c0 files). Note: This correction is incorporated in the POA_CALFOS pipeline, no further correction is necessary for data reduced with the POA_CALFOS pipeline.

Improved algorithm for accumulator "wrap-around" correction.

(30 December 1997) The 16-bit FOS accumulators were limited to 65536 counts in any individual read out before they would "wrap around". The existing STSDAS routine unwrap can be used to fix many cases, but is not always successful. We provide here IDL coding ( of a more robust algorithm that has been used by FOS team members to unwrap pathological cases. The code is provided "as-is" without warranty.

Pre-COSTAR Theoretical PSFs.

(21 January 1998) FOS theoretical Point Spread Functions (PSFs) were calculated with TIM for the pre-COSTAR era and presented in FOS ISR 104. We present a listing of the PSFs available in the HST database as described in that document.

Pre-COSTAR Theoretical LSFs.

FOS theoretical Line Spread Functions (LSFs) were calculated from TIM model PSFs for the pre-COSTAR era and presented in FOS ISR 104.

CDBS FOS pages.

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Last modified: Wed Jul 14 16:28:33 MET DST 1999