Opened 11 years ago

Closed 9 years ago

#232 closed task (fixed)

Validate 2009 calibration

Reported by: mark1 Owned by: mggr
Priority: immediate Milestone:
Component: ARSF Keywords:
Cc: mggr Other processors:

Description (last modified by mggr)

Specim calibrated the Eagle and Hawk sensors at the start of the 2009 season. We need to validate the calibration as best we can - this will primarily require an independent verification by FSF.

Mismatches in the overlap region between Eagle and Hawk still exist, as in previous years:
Eagle/Hawk spectra using 2009 calibration over water

Attachments (3)

2009water.png (5.4 KB) - added by mark1 11 years ago.
Eagle/Hawk spectra using 2009 calibration over water
2007vs2009_percentage_difference_eagle.png (41.3 KB) - added by mark1 10 years ago.
Percentage difference of data processed with 2009 calibration to 2007 calibration - Eagle
2007vs2009_percentage_difference_hawk.png (38.1 KB) - added by mark1 10 years ago.
Percentage difference of data processed with 2009 calibration to 2007 calibration - Hawk

Download all attachments as: .zip

Change History (7)

Changed 11 years ago by mark1

Eagle/Hawk spectra using 2009 calibration over water

comment:1 Changed 11 years ago by mggr

  • Description modified (diff)

comment:2 Changed 11 years ago by mggr

Comparison of the 2007 vs 2009 calibrations shows significant changes at some wavelengths. As we currently have no independent verification, we can only assume these changes are correct..

Mark: could you add the gnuplot images you made to this ticket?

Changed 10 years ago by mark1

Percentage difference of data processed with 2009 calibration to 2007 calibration - Eagle

Changed 10 years ago by mark1

Percentage difference of data processed with 2009 calibration to 2007 calibration - Hawk

comment:3 Changed 10 years ago by mark1

An Eagle and Hawk image have been processed with both the 2007 and 2009 calibrations. The difference between the 2007 and 2009 radiance values, for a sample of pixels, has been converted to percentage of the 2007 values, and is graphed below.

Percentage difference of data processed with 2009 calibration to 2007 calibration - Eagle

Percentage difference of data processed with 2009 calibration to 2007 calibration - Hawk

comment:4 Changed 9 years ago by mggr

  • Resolution set to fixed
  • Status changed from new to closed

We now have internal calibrations and the means to test them. The Specim wavelengths appear correct to within subpixel error. Radiance multipliers are within 5%, which is pretty fair given our measurement error and uncertainty about Specim's setup.

The overlap regions will still have poor calibration as they are very low on signal to noise ratio. We can now quantify this.

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