Version 2 (modified by mggr, 13 years ago) (diff)

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Jobs to do before a new flight season starts

Lever arms

If required, perform a survey of the positions of the instruments relative to the GPS antenna. We need sufficient information to compute the positions of:

  • the GPS antenna(s)
  • the LIDAR scanner (a measurement to the reference point on the case is sufficient)
  • the RCD camera (a measurement to the reference point on the case is sufficient)
  • Eagle
  • Hawk
  • TABI, CASI or any other imaging instrument that is installed

In all cases, a measurement to a suitable reference point on the casing of the instrument, plus an engineering diagram of the instrument, is sufficient. We have these diagrams for the Specim and Leica instruments.

These values should be recorded at:

Hyperspectral

Boresight calibration

(explanation + insert link to boresight doc here)

Results should be recorded at Processing/BoresightCalibration

Radiometric and spectral calibration

There should have been one of these prior to the season starting. It must determine the spectral calibration of the instruments (what wavelength maps to what band) and the radiometric calibration (what gain to apply to map DN to radiance).

  1. Ensure the wavelength files on the Specim are updated to the current season and the old ones are destroyed or moved off the system.

LIDAR

Boresight calibration

Ideally we should use the Gloucester city calibration area as it has much more vertical relief. However, at the time of writing (2011), the area is not yet fully ready. Instead, we can use the Little Rissington site for the time being.

Scan encoder

The scan encoder measures the angle the mirror is at. At the start of the season, we should check the "centre/nadir" position is unchanged.

The procedure to check the scan encoder:

  • Start up the system on the ground (no GPS or installation required)
  • Run BIT mode
  • Turn off 'Position In' switch on the front panel
  • This will snap the mirror to the centre
  • Then read F4's tick column,it should show the real scan offset and it should be within ± 500 ticks from the -10800 value
  • Don't forget to switch on 'Position In' when you finish testing