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+--- Thread: How can I avoid the overcorrection (bright terrain ridges)? (/showthread.php?tid=36)
How can I avoid the overcorrection (bright terrain ridges)? - rese_support - 30-Sep-2014
When processing imagery in rugged terrain I get some bright areas with very high reflectance values that are obviously overcorrected. The overcorrection usually occurs in areas with steep slopes oriented away from the sun. These areas with a high local solar incidence angle (or low local solar elevation angle) appear dark in the illumination image cos(solar_incidence) that is automatically generated. In these areas the reflectance shows a behavior that depends on the illumination and viewing conditions (the bidirectional reflectance distribution function, BRDF). There is no general solution to this problem. However, an empirical correction method is implemented in ATCOR which takes care of BRDF effects causing such overcorrections.