<div dir="ltr"><p class="MsoNormal" style="font-family:arial,sans-serif;font-size:13px;text-align:justify"><span lang="EN-GB" style="font-family:Calibri">Dear all,</span></p><p class="MsoNormal" style="font-family:arial,sans-serif;font-size:13px;text-align:justify">
<span lang="EN-GB" style="font-family:Calibri"> </span></p><p class="MsoNormal" style="font-family:arial,sans-serif;font-size:13px;text-align:justify"><span lang="EN-GB" style="font-family:Calibri">I am recent GRASS GIS user who is trying to run the <i>i.atcorr</i> module to atmospherically correct a Landsat ETM+ image in GRASS 7 (on MacBook Pro, Mavericks OSX). This image has been already converted to reflectance with <i>i.landsat. toar</i>. I also use a DEM file obtained from ASTER GDEM. All these files are projected to UTM zone 36 S.</span></p>
<p class="MsoNormal" style="font-family:arial,sans-serif;font-size:13px"><span lang="EN-GB"> </span></p><p class="MsoNormal" style="font-family:arial,sans-serif;font-size:13px"><span lang="EN-GB" style="font-family:Calibri">I have followed the steps described in the manual and everything seems to be fine except that the process returns an empty raster (all raster values equal to NoData).</span></p>
<p class="MsoNormal" style="font-family:arial,sans-serif;font-size:13px"><span lang="EN-GB" style="font-family:Calibri"> </span></p><p class="MsoNormal" style="font-family:arial,sans-serif;font-size:13px"><span lang="EN-GB" style="font-family:Calibri"> This is the command:</span></p>
<p class="MsoNormal" style="font-family:arial,sans-serif;font-size:13px"><span lang="EN-GB" style="font-family:Calibri"> </span></p><p class="MsoNormal" style="font-family:arial,sans-serif;font-size:13px"><span lang="EN-GB" style="font-family:Calibri">i.atcorr –r –a input= LakeChirwaN-REFL1@Malawi parameters=/Users/Xavi/Desktop/LCDM.txt output=LakeChirwaN_REFL1_ATCORR</span></p>
<p class="MsoNormal" style="font-family:arial,sans-serif;font-size:13px"><span lang="EN-GB" style="font-family:Calibri"> </span></p><p class="MsoNormal" style="font-family:arial,sans-serif;font-size:13px"><span lang="EN-GB" style="font-family:Calibri">And the LCDM file looks like this:</span></p>
<p class="MsoNormal" style="font-family:arial,sans-serif;font-size:13px"><span lang="EN-GB" style="font-family:Calibri"> </span></p><p class="MsoNormal" style="font-family:arial,sans-serif;font-size:13px"><span lang="EN-GB" style="font-family:Calibri">8 -- Landsat ETM+</span></p>
<p class="MsoNormal" style="font-family:arial,sans-serif;font-size:13px"><span lang="EN-GB" style="font-family:Calibri">5 26 7.487 </span><span lang="EN-US" style="font-family:Calibri">35.753 -14.414 -- </span><span lang="EN-US" style="font-family:Calibri;color:rgb(38,38,38)">month day hh.ddd longitude latitude</span><span lang="EN-US" style="font-family:Calibri"></span></p>
<p class="MsoNormal" style="font-family:arial,sans-serif;font-size:13px"><span lang="EN-US" style="font-family:Calibri">1 -- Atmospheric model: tropical</span></p><p class="MsoNormal" style="font-family:arial,sans-serif;font-size:13px">
<span lang="EN-US" style="font-family:Calibri">0 -- Visibility</span></p><p class="MsoNormal" style="font-family:arial,sans-serif;font-size:13px"><span lang="EN-US" style="font-family:Calibri">-0.009 -- Aerosol Optical Depth 550 nm</span></p>
<p class="MsoNormal" style="font-family:arial,sans-serif;font-size:13px"><span lang="EN-US" style="font-family:Calibri">-0.650 </span><span lang="EN-US" style="font-family:Calibri">-- Mean target elevation (in Km) *-1</span></p>
<p class="MsoNormal" style="font-family:arial,sans-serif;font-size:13px"><span lang="EN-US" style="font-family:Calibri">-1000 -- Sensor height (on board a satellite)</span></p><p class="MsoNormal" style="font-family:arial,sans-serif;font-size:13px">
<span lang="EN-US" style="font-family:Calibri">61 -- Sensor band (ETM+ band 1)</span></p><p class="MsoNormal" style="font-family:arial,sans-serif;font-size:13px"><br></p><p class="MsoNormal" style="font-family:arial,sans-serif;font-size:13px">
<span lang="EN-GB" style="font-family:Calibri"> </span></p><p class="MsoNormal" style="font-family:arial,sans-serif;font-size:13px"><span lang="EN-GB" style="font-family:Calibri">Could someone give help me on this please?</span></p>
<p class="MsoNormal" style="font-family:arial,sans-serif;font-size:13px"><span lang="EN-GB" style="font-family:Calibri"> </span></p><p class="MsoNormal" style="font-family:arial,sans-serif;font-size:13px"><span lang="EN-GB" style="font-family:Calibri">Thanks in advance!!</span></p>
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