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Calibration Reference Data System

Reference files used by the WFC3 calibration pipeline (calwf3 and PyDrizzle/MultiDrizzle) are updated on a regular basis. Current reference files files can be retrieved from the HST archive, or downloaded directly from the iref directory. Note that FTP access is browser dependent: Safari does not work; Firefox or Chrome may or may not work depending on the Operating System. If you cannot download the files via Firefox or Chrome, you can try using a standalone FTP tool or accessing the ftp site directly (ftp ftp.stsci.edu) with 'anonymous' (without quotes) as your username and your email address as your password.

To retrieve a file from the archive, click in the file name. For details on how to correctly set up the Archive retrieval options for reference files, check our Help page.

To receive e-mail notifications of deliveries of new reference files, you can subscribe to instrument specific mailing lists. More.

New tools for exploring WFC3 Reference Files are now available at https:/hst-crds.stsci.edu. To get a listing of the reference files you're interested in, click on 'wfc3' then select the filetype. Use the names below in the Header Keyword column as a guide.

Reference File Type File Suffix Header Keyword Detector
Bias Images
Additive stationary pattern in the electronic zero point of the CCDs. More...
BIA BIASFILE UVIS
Dark Images
Additive noise due to thermal effects. More...
DRK DARKFILE Both
Flat-Field Images
Variations in the sensitivity of the detectors. More...
PFL PFLTFILE Both
Linearity Correction Files
Non-linearity effects in the IR detector. More...
LIN
NLINFILE
IR
Bad Pixel Tables
All known permanently bad pixels. More...
BPX
BPIXTAB
Both
Detector Characteristics Tables
Detector parameters such as readnoise, gain, and bias levels. More...
CCD
CCDTAB
Both
Overscan Region Tables
Overscan (UVIS) or reference pixel (IR) areas. More...
OSC
OSCNTAB
Both
Cosmic Ray Rejection Tables
Parameters for performing image stacking. More...
CRR
CRREJTAB
Both
MultiDrizzle Parameter Table
Input parameters for combining associated exposures. More...
MDZ
MDRIZTAB
Both
Pixel Area Correction Tables
Map of pixel area variation across the field of view. More...
PAM
  -   Both detectors
Synphot Throughput Files
Synphot is the STSDAS synthetic photometry package. More...
  -     -   Both detectors
Image Photometry Table
Parameters for performing photometry correction More...
IMP
IMPHTTAB
Both
Post-Flash Image File
Application of a post-flash image. More...
FLS FLSFILE UVIS
Detector-to-Image Correction File
2-D look-up table of astrometric corrections for shifts caused by the lithographic-mask pattern More...
D2I D2IMFILE UVIS
Non-polynomial Filter Dependent Distortion File
2-D look up table containing the non-polynomial filter-dependent part of the distortion correction. More...
NPL NPOLFILE UVIS

Tables used to calculate SIP coefficients
(see Drizzlepac/Astrodrizzle Web Pages)

Reference File Type File Suffix Header Keyword Detector
Image Distortion Coefficient Tables
Geometric distortion models. More...
IDC IDCTAB Both

Currently not supported

Reference File Type File Suffix Header Keyword Detector
Analog-to-Digital Tables
Currently disabled
A2D ATODTAB N/A