THEMATIC MAPPER: DETAILED RADIOMETRIC AND GEOMETRIC CHARACTERISTICS.

The paper is in abstract form. It discusses those radiometric characteristics of the Landsat 4 Thematic Mapper (TM) that can be established without absolute calibration or spectral data. Subscenes of radiometrically raw data (B-data) were examined on an individual detector basis; areas of uniform radiance were used to characterize subtle radiometric differences and noise problems. The effective resolution in radiance is degraded by about a factor of two by irregular width of the digital levels. Several detectors have a change of gain with a period of several scans, the largest effect is about 4%. The geometric fidelity of the GSFC filmwriter used for Thematic Mapper (TM) images was assessed by measurement with accuracy better than three micrometers of a test grid.