Airborne Multi-angle Imaging SpectroRadiometer (AirMISR) Data from the KONza Validation EXperiment (KONVEX)

Unlike the satellite-borne MISR instrument, which has nine cameras oriented at various angles, AirMISR uses a single camera in a pivoting gimbal mount. A data run by the ER-2 aircraft is divided into nine segments, each with the camera positioned to a MISR look angle. The gimbal rotates between successive segments, such that each segment acquires data over the same area on the ground as the previous segment.

This process is repeated until all nine angles of the target area are collected. The swath width, which varies from 11 km in the nadir to 32 km at the most oblique angle, is governed by the camera's instantaneous field-of-view of 7 meters cross-track x 6 meters along-track in the nadir view and 21 meters x 55 meters at the most oblique angle. The along-track image length at each angle is dictated by the timing required to obtain overlap imagery at all angles, and varies from about 9 km in the nadir to 26 km at the most oblique angle.

Thus, the nadir image dictates the area of overlap that is obtained from all nine angles. A complete flight run takes approximately 13 minutes. The 9 camera viewing angles are:0 degrees or nadir26.1 degrees, fore and aft45.6 degrees, fore and aft60.0 degrees, fore and aft70.5 degrees, fore and aft For each of the camera angles, images are obtained at 4 spectral bands.

The spectral bands can be used to identify vegetation and aerosols, estimate surface reflectance and ocean color studies. The center wavelengths of the 4 spectral bands are:443 nanometers, blue555 nanometers, green670 nanometers, red865 nanometers, near-infrared Two types of AirMISR data products are available - the Level 1 Radiometric product (L1B1) and the Level 1 Georectified radiance product (L1B2).