HST Calibration Reference Data System (CRDS)

 

NOTICE

The term "operational" has changed to "latest" when referring to the newest CRDS Context available. For more information, please refer to the user guide.

Documentation updates are ongoing. If something in the user guide is ambiguous, please reach out to the CRDS team or file a help desk ticket.


 

Obtain Best Reference Files

  1. Using the Command Line
  2. From Dataset ID or FITS Header Upload
  3. Exploring with Instrument Parameters

Reference File Database Services

  1. Server Environment Package Versions
  2. Browse Database
  3. Recent Activity

Latest References (under context hst_1226.pmap)


Context History (more history, all contexts, build contexts)

Start Date Context Status Description
2025-04-01 hst_1226.pmap latest Since 2019, IR bad pixel tables and superdarks incorporate a new time-dependence characteristic to the pixel quality for better calibration and flagging and tracking bad pixel behavior. These behaviors include hot and unstable pixels and whether any bad pixel has regained its stability since launch. A litany of circular aberrant regions called blobs have appeared in IR images. These blobs are regions of lower sensitivity that appear due to bits of epoxy from the CSM motor shafts depositing onto the mirror. Tracking and flagging these blobs in the IR bad pixel table is therefore imperative so that they may be masked in any science images where they may appear. Information regarding blobs can be found in WFC3 ISR 2018 06. This IR bad pixel table with a USEAFTER of Jan 04 2025 includes a blob that appeared on MJD 60679.7772, that was not corrected for in the previous IR bad pixel table.
2025-03-28 hst_1225.pmap archived Delivery of new STIS CCD bias and dark reference files for CCD data taken between February 19 and March 19, 2025. The files were generated from data taken in the same time frame under STIS calibration programs 17632, 17629, and 17630.
2025-03-26 hst_1224.pmap archived Updating the FUV-MAMA TDSTAB reference file to reflect the latest time-dependent sensitivity trends. A new breakpoint was added at 01-24-2020 to accommodate an increase in sensitivity of about 2 percent in the most recent TDS data. This breakpoint was determined using an optimization routine in our new TDS code.
2025-03-26 hst_1223.pmap archived The reason for delivery is: Delivering new ACS WFC superdarks and CTE-corrected superdarks for the 2024-11-19, 2025-01-18, and 2025-02-11 anneal periods. The threshold for unstable pixels was updated due to a change in the exposure time of ACS WFC calibration long darks. Shorter exposure times, 1000.5s to 650.5s, led to an artificial drop in the number of unstable pixels, so the threshold for instability was changed to compensate in these. These new 650.5s superdarks have the correct number of unstable pixels flagged.