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Bias, Overscan
Gain, Noise


Bias, Overscan
Gain, Noise




Shading, accuracy


Encircled energy

Internal Count Rates






Stray Light

Light leak
Filter dust

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Last updated
27 March 2002 10:02:37

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Calibration Results and Products

A brief description of the chip formats used in the following sections is available.

  1. Detector Properties
    1. WFC
      [Build 1]
      1. Noise problems
      [Build 2]
      [Build 3]
      1. Bias and overscan analysis (Jun 2000)
      [Build 4]
      1. Bias and overscan analysis (Aug 2001)
      2. Gain, noise, linearity, saturation (Apr-Jul 2001)
    2. HRC
      [Build 1]:
      1. Darks
      2. Bias frames
      3. Gain, noise, linearity, saturation (Apr-Jul 2001)
      4. Gain measurements (Mar 1999)
      5. Charge transfer efficiency (TV1)
      6. Bias and overscan analysis (Jun 2000)
      [Build 2]
      1. Gain measurements (Feb 1998)
      2. Charge transfer efficiency
      3. Quantum efficiency hysterises
    3. SBC
      1. Flats (Feb-Mar 1999):
        Raw and "P-flats" for all filters, features, wavelength response, repeatability, defect level.
      2. Darks (Jul 2001):
        Dark rate and hot pixels vs TSBC.
      3. Darks (Jun 1999):
        Dark rate, vs time, vs TSBC, vs MCP current, dark structure, model, hot pixels.
      4. Throughput:
        Calibration, monitor vs time, throughput vs filter.

  2. Shutter Performance (WFC, HRC)
    1. Shading and accuracy (Feb 2001)
    2. Shading and accuracy (Jun 2000)

  3. Geometry (WFC, HRC, SBC)
    FOV location, plate scale, distortions
    1. HRC#1 and WFC#3 (Jun 2000)

  4. PSF Characterization (WFC, HRC, SBC)
    Ground results, encircled energy (EE), field position, PSF wings and halo vs wavelength.
    1. Encircled Energy Verification (WFC, HRC, SBC) (Oct 2001)
    2. Image stability (WFC, HRC, SBC) :
      Experimental setups, motions found, debug results: causes of image motion.
    3. Coronograph and Fastie finger performance (HRC)
      Location of coronographic spots and Fastie finger, PSF suppression.
    4. HRC and SBC Confocality (Sep 2000)

  5. Photometric Calibration : Field Center
    1. Throughput (HRC, WFC)

  6. Photometric Calibration : Whole Field
    1. Fringing
    2. Internal calibration system verification:
      WFC, HRC, and SBC count rates vs filter, comparison with model, D2 lamp degradation, improvements to D2 lamp filter.
      1. On-orbit tungsten lamps (Mar 2002)
      2. Deuterium and tungsten lamps (Jan-Aug 2001, HRC#1+WFC#4)
      3. Tungsten lamps (Jun 2000, HRC#1+WFC#3, BATC/Ambient)
      4. Tungsten lamps (Mar 1999, HRC#1, GSFC/TV1)
      5. Deuterium lamp (SBC)(Jul 2001)
      6. Deuterium lamp (SBC)(Mar 1999)

  7. Flash Calibration (HRC, WFC)(Nov 2001)

  8. Dispersers (Prisms and Grism)
    Relative pixel vs wavelength, comparison to model, Flux vs order distribution.
    1. Prism (PR200L : HRC) (Apr 2001)
    2. Grism (G800L : HRC, WFC) (Apr 2001)
    3. UV Prisms (SBC, HRC) (May 1999)

  9. Ramp Filter Characterization (WFC, HRC)
    Wheel position vs wavelength

  10. Polarimetric Calibration (WFC, HRC)
    1. Instrumental Polarization (Nov 2001)

  11. Stray Light Characterization (WFC, HRC)
    Mask reflections, filter and window ghosts, WFC gap behavior, dewar reflections, enclosure.
    1. Enclosure light leaks (HRC, WFC) (Sep-Nov 2001)
    2. Dust on filters (HRC, WFC) (Jun 2000)

  12. Filter throughput (component level results)