While airborne instruments can be well calibrated in the laboratory, the calibration may shift due to the flight dynamic conditions and temperature variations between the lab and the airborne platform. Moreover, the airborne instrument is subject to atmospheric path radiance, absorption, and scattering. The solution often requires ground truthing techniques.  

OKSI designs, conducts, and provides ground truth measurements and tools. These include large calibration panels with well charaterized diffuse gray level, man-portable sensors, and special field rigs for carrying overhead sensors that view the ground from above. In addition, radiometers, and full meteorolical stations can be provided for a more comprehensive analysis of the airborne data.  

All such measurements are designed to provide the ground truth for assessing the performance of the airborne sensor and comparing the airborne data to the known ground reference targets.