How to read the Landsat ETM+ calibration coefficients? - Printable Version +- ReSe User Support Forum (https://forum.rese-apps.com) +-- Forum: Frequently Asked Questions (https://forum.rese-apps.com/forumdisplay.php?fid=1) +--- Forum: ATCOR-4 (FAQ) (https://forum.rese-apps.com/forumdisplay.php?fid=5) +--- Thread: How to read the Landsat ETM+ calibration coefficients? (/showthread.php?tid=37) |
How to read the Landsat ETM+ calibration coefficients? - rese_support - 30-Sep-2014 The Landsat-7 ETM+ calibration coefficients are specified with the unit [W m[sup]-2[/sup] sr[sup]-1[/sup] micron[sup]-1[/sup]] in the metadata file. Multiply the coefficients in the metadata file by 0.1 to convert into [mW cm[sup]-2[/sup] sr[sup]-1[/sup] micron[sup]-1[/sup]].2) Landsat-7 ETM+ has commandable gain settings (low: g=1, high: g=1.5, for the solar bands, and high: g=2 for the thermal band). The question is how to consider this for the c0, c1 calibration coefficients.The radiance-DN relationship for sensors with gain setting g is L = c0 + {c1/g} * DN However, in the Landsat-7 metadata file the slope (gain) value c1 is already adapted to g=1. Therefore, multiply the value by the factor 0.1 to convert the Landsat radiance unit (see Question 2) into the ATCOR unit [mW cm[sup]-2[/sup] sr[sup]-1[/sup] micron[sup]-1[/sup]], specify a gain setting g=1 in the ATCOR panel. |