1. Overall ArchitectureOverall Architecture Use of AssociationsUse of Associations Outline of ProcessingOutline of Processing Reuse of CALACS and CALNIC CodeReuse of CALACS and CALNIC Code Processing Steps and KeywordsProcessing Steps and Keywords Reference FilesReference Files WFC3 Pipeline Calibration

2. WFC3 PIPELINE PDR H. Bushouse February 13, 2001CALWF32 CALWF3 Architecture Code written in ANSI CCode written in ANSI C Use CVOS and HSTIO interfaces to IRAF/TABLES librariesUse CVOS and HSTIO interfaces to IRAF/TABLES libraries All run-time data files in FITS format with extensionsAll run-time data files in FITS format with extensions Exposures consist of multiple-extension IMSETsExposures consist of multiple-extension IMSETs Use associations to process and combine related exposuresUse associations to process and combine related exposures

3. WFC3 PIPELINE PDR H. Bushouse February 13, 2001CALWF33 CALWF3 Outline Maximal reuse of ACS and NICMOS calibration softwareMaximal reuse of ACS and NICMOS calibration software CALWF3 based on CALACS flow modelCALWF3 based on CALACS flow model Includes single and multiple image operations within one shellIncludes single and multiple image operations within one shell UVIS and IR images treated as similarly as possibleUVIS and IR images treated as similarly as possible –UVIS identical to ACS WFC –IR similar to NICMOS Grism/Prism images receive 2-D processing only; spectral extraction tools to be supplied by ST-ECF (as is the case for NICMOS & ACS)Grism/Prism images receive 2-D processing only; spectral extraction tools to be supplied by ST-ECF (as is the case for NICMOS & ACS)

4. WFC3 PIPELINE PDR H. Bushouse February 13, 2001CALWF34 Basic Functions Apply instrumental calibrations to individual imagesApply instrumental calibrations to individual images –Includes handling of binned and subarray images Perform various types of combining for associated imagesPerform various types of combining for associated images –Combine UVIS CR-Splits and IR MultiAccums –Sum Repeat-Obs for UVIS and IR images –Drizzle Dithered UVIS and IR images Interface to Drizzle module currently in development by ACS team for CALACS; adoption of CALACS backbone will allow for easy CALWF3 integrationInterface to Drizzle module currently in development by ACS team for CALACS; adoption of CALACS backbone will allow for easy CALWF3 integration Drizzle module can be used to perform geometric correctionsDrizzle module can be used to perform geometric corrections

5. WFC3 PIPELINE PDR H. Bushouse February 13, 2001CALWF35 Use of Associations Associations will be used for:Associations will be used for: –CR-Splits –Repeat-Obs –Dither patterns –All possible combinations of the above Associations will not be used for:Associations will not be used for: –Mosaic patterns (logically-related exposures specified across >1 exposure logsheet line) CALWF3 will use list of exposures in association table to identify files that need to be processed as groups & subgroupsCALWF3 will use list of exposures in association table to identify files that need to be processed as groups & subgroups

6. WFC3 PIPELINE PDR H. Bushouse February 13, 2001CALWF36 ACS2D DQI Nonlin Dark Flat PhotCALNICA CALACS Flow Model Another Set of CR-SPLITS? Detector CCD MAMA Another Image in Association? CRCORR ACSREJ CR Rejection Yes ACS2D Dark Flat Shad Phot ACSCCD AtoD DQI Blev Bias Another Image in CR-SPLIT? RPTCORR ACSSUM Yes ACSDTH (Drizzle) Yes DTHCORR IR

7. WFC3 PIPELINE PDR H. Bushouse February 13, 2001CALWF37 CALWF3 Flow Diagram Detector UVIS IR WF3IR Zoff DQI Blev Bias Nlin Dark Flat Phot Another Image in Association? WF3CCD AtoD DQI Blev Bias Another Image in CR-SPLIT? CRCORR WF3REJ CR Rejection Yes WF3CCD Dark Flat Shad Phot Another Set of CR-SPLITS? Another Set of CR-SPLITS? Yes DTHCORR RPTCORR WF3SUM Yes WF3DTH (Drizzle) ?

8. WFC3 PIPELINE PDR H. Bushouse February 13, 2001CALWF38 Code Reuse CALACS backbone used for overall flow controlCALACS backbone used for overall flow control CALACS module reuse:CALACS module reuse: –acsccd: CALWF3 UVIS processing –acsrej: CALWF3 UVIS CR-Split combination –acssum: CALWF3 UVIS and IR Repeat-Obs combination –acsdth: CALWF3 UVIS and IR Dither combination CALNICA reuse:CALNICA reuse: –All applicable MultiAccum-mode calibration modules No CALNICB reuse:No CALNICB reuse: –All image combination done via CALACS and Drizzle methods Backwards compatibility with CALACS and CALNIC allows for easy implementation of future developments that are of value to WFC3 (e.g. NICMOS post-SAA persistence and pedestal corrections, ACS Drizzle development, etc.)Backwards compatibility with CALACS and CALNIC allows for easy implementation of future developments that are of value to WFC3 (e.g. NICMOS post-SAA persistence and pedestal corrections, ACS Drizzle development, etc.)

9. WFC3 PIPELINE PDR H. Bushouse February 13, 2001CALWF39 Required Upgrades UVIS binned imagesUVIS binned images –STIS: calstis rebins reference data on-the-fly to match science images –ACS: no binning capabilities; reference data read line-by-line –WFC3: difficult to merge STIS on-the-fly rebinning with ACS line-by- line I/O; will be handled instead via binned reference data IR subarray imagesIR subarray images –necessary for short exposures of bright standards –not supported in CALNIC; will use algorithms from CALACS WFC IR overscan subtractionIR overscan subtraction –used to track bias levels in each non-destructive readout –not supported in CALNIC; will use algorithms from CALACS WFC Interface to DrizzleInterface to Drizzle –currently under development for CALACS

10. WFC3 PIPELINE PDR H. Bushouse February 13, 2001CALWF310 CALWF3 UVIS Cal Steps Input Files Processing Step Keyword Switch Output File _asn or _raw CCDTAB Compute Statistical Errors (initialize ERR array) N/A BPIXTAB Assign Static DQ Flags (initialize DQ array) DQICORR ATODTAB A-to-D Correction ATODCORR OSCNTAB Overscan Bias Level Subtraction BLEVCORR BIASFILE Bias Image Subtraction BIASCORR_blv_tmp _blv_tmpCRREJTAB Cosmic-Ray Rejection CRCORR_crj_tmp

11. WFC3 PIPELINE PDR H. Bushouse February 13, 2001CALWF311 CALWF3 UVIS Steps (cont.) Input Files Processing Step Keyword Switch Output File _crj_tmpDARKFILE Dark Current Subtraction DARKCORR PFLTFILELFLTFILE Flatfield Correction FLATCORR SHADFILE Shutter Shading Correction SHADCORR PHOTTAB Compute Photometric Parameters (populate PHOTxxxx keywords) PHOTCORR Compute Image Statistics STATFLAG _flt or _crj

12. WFC3 PIPELINE PDR H. Bushouse February 13, 2001CALWF312 CALWF3 IR Cal Steps Input Files Processing Step Keyword Switch Output File _asn or _raw Zeroth-read Signal Correction ZSIGCORR Zeroth-read Subtraction ZOFFCORR BPIXTAB Assign Static DQ Flags (initialize DQ arrays) DQICORR OSCNTAB Overscan Bias Level Subtraction BLEVCORR Compute Statistical Errors (initialize ERR arrays) N/A

13. WFC3 PIPELINE PDR H. Bushouse February 13, 2001CALWF313 CALWF3 IR Cal Steps (cont.) Input Files Processing Step Keyword Switch Output File DARKFILE Dark Current Subtraction DARKCORR NLINFILE Non-Linearity Correction NLINCORR PHOTTAB Compute Photometric Parameters (populate PHOTxxxx keywords) PHOTCORR CRREJTAB Cosmic-Ray Rejection (also combines readouts) CRCORR PFLTFILELFLTFILE Flatfield Correction FLATCORR Compute Image Statistics STATFLAG _ima and _crj

14. WFC3 PIPELINE PDR H. Bushouse February 13, 2001CALWF314 CALWF3 Image Combining Input Files Processing Step Keyword Switch Output File _flt or _crj Sum Repeat-Obs Images RPTCORR_sfl _flt or _crj or _sfl IDCTABDITHTAB Combine Dithered Images 1 DITHCORR_dth 1 DITHCORR currently a stub in CALACS; drizzle algorithm development is in progress by ACS & SSG teams

15. WFC3 PIPELINE PDR H. Bushouse February 13, 2001CALWF315 CALWF3 Reference Images Image Name SuffixDescriptionUVISIR Selection Criteria BIASFILEbiaBias* DETECTOR GAIN BINAXIS 1 DARKFILEdrk Dark Current ** DETECTOR GAIN BINAXIS 1 SAMP_SEQ NLINFILElin Non-Linearity Coefficients *DETECTOR PFLTFILEpfl Pixel-to-Pixel Flat Field ** DETECTOR FILTER BINAXIS 1 LFLTFILElfl Low-order Flat Field ** DETECTOR FILTER BINAXIS 1 SHADFILEshd Shutter Shading Correction *DETECTOR BINAXIS 1 1 Separate reference images will be maintained in CDBS for each binning mode.

16. WFC3 PIPELINE PDR H. Bushouse February 13, 2001CALWF316 CALWF3 Reference Tables Table Name SuffixDescriptionUVISIR Selection Keywords Selection Columns Parameter Columns ATODTABa2d Analog-to-Digital Correction *AMPGAINREF_KEYREF_KEY_VALUENELEMATOD BPIXTABbpx Bad Pixel Table **DETECTORPIX1PIX2LENGTHAXISVALUE CCDTABccd CCD Parameters **DETECTORAMPCHIPGAINOFSTBINAXIS1BINAXIS2ATODGAINBIASREADNSESATURATEAMPXAMPY

17. WFC3 PIPELINE PDR H. Bushouse February 13, 2001CALWF317 CALWF3 Ref Tables (cont.) Table Name SuffixDescriptionUVISIR Selection Keywords Selection Columns Parameter Columns CRREJTABcrr Cosmic-Ray Rejection Parameters**DETECTORCRSPLITMEANEXPSCALENSEINITGUESSSKYSUBCRSIGMASCRRADIUSCRTHRESHBADINPDQCRMASK IDCTABidc Image Distortion Coefficients**DETECTORFUNCTYPENCOEFF1COEFF1[ncoeff1]NCOEFF2COEFF2[ncoeff2]

18. WFC3 PIPELINE PDR H. Bushouse February 13, 2001CALWF318 CALWF3 Ref Tables (cont.) Table Name SuffixDescriptionUVISIR Selection Keywords Selection Columns Parameter Columns OSCNTABosc Overscan Parameters **DETECTORAMPCHIPBINXBINY NX NY TRIMX[1,2]TRIMY[1,2]VX[1,2]VY[1,2]BIASSECTA[1,2]BIASSECTB[1,2] PHOTTABpht Photometry Parameters **DETECTORFILTERNELEMWAVELENGTHTHROUGHPUT

19. WFC3 PIPELINE PDR H. Bushouse February 13, 2001CALWF319 Test Plan A comprehensive test plan will be created for UVIS and IR instrumental calibrations, as well as all image combination methods, to be executed and evaluated by WFC3 IPTA comprehensive test plan will be created for UVIS and IR instrumental calibrations, as well as all image combination methods, to be executed and evaluated by WFC3 IPT Tests will include:Tests will include: –Correct selection and sequence of calibration steps depending on science data input –Proper trapping and handling of common failure modes (e.g. missing, inappropriate reference data files, missing assocation members, missing or invalid keyword values, etc.) –Verification of intended scientific results from each operation –Correct generation of trailer files