Instrument Calibration

The instruments are returned to their respective manufacturer (Specim and Leica) at the end of each flying season for annual maintenance and calibration. We also carry out our own in-house calibration of the Hyperspectral sensors at ARSF Gloucester.

Leica Calibration

The ALS50-II LiDAR and the RCD105 camera are calibrated at Leica Geosystems offices in Heerbrrugg, Switzerland.

Leica LiDAR

As part of the annual calibration Leica fly a test flight to check the system and provide us with a Calibration Certificate. An Intensity Based Range Correction (IBRC) file is generate for the sensor. This table is used to correct for effect of varying range based on return signal strength. Since 2012 Leica provide us with both a single IBRC file and a Dual IBRC. The dual table allows for improved range correction when a lower scan rate is used during data collection.

The remaining calibration parameters provided by Leica are subsequently calculated/verified during the Boresight procedure.

The latest calibration certificate for the ALS50-II can be found here​.

Additional calibration files provided by leica, which are used during the LiDAR processing, can be found below:

Single IBRC Table: SN89_IBRC-25-Jan-2012.txtSN89_IBRC-25-Jan-2012.txt
Dual IBRC Table: SN89_IBRC_Dualtable_20120125.csv​

Leica RCD

The latest calibration certificate for the RCD105 can be found here​.

Additional calibration files provided by leica, which are used during the camera processing, can be found below:

Bias correction: CH39_021_060_019_RGB_20100109_G3bl.tif and CH39_021_060_019_RGB_20100109_G3sl.tif
System repsonse correction: CH39_021_060_019_RGB_20100109_G3gl.tif
Colour Processing: CH39_021_060_019_RGB_20100109_G3pl.txt