Landsat thematic mapper reflective-band radiometric artifacts

Radiometric "artifacts" are known to be present to varying degrees in the reflective-band imagery from both Landsat-4 and Lansat-5 Thematic Mappers (TMs). The most common artifacts are known as scan-correlated shift (SCS), memory effect (ME), and coherent noise (CN). The characterization and correction of these artifacts has been performed for both the Landsat-4 and Lansat-5 TMs. SCS is a sudden shift in bias that can be as large as 2 DN. However, this artifact can be accurately quantified and easily removed from imagery using a line-by-line bias subtraction. ME causes the detector response to undershoot after a sudden transition from a bright target to a dark target. For large transitions, this can cause a 2% radiometric error. This artifact can be removed through a spatial filtering operation. Lastly, CN is a periodic pattern that is most often seen in homogeneous portions of TM imagery. The amplitude of this noise artifact is quite small, less than 0.5 DN. While CN has been accurately characterized, a correction procedure is not recommended, due to the small amplitude of this artifact. Recommendations are given for proper processing of TM imagery to remove the effects of these artifacts.