https://community.esri.com/t5/arcmap-questions/topographic-correction-in-antarctica/m-p/1034846#M2117 <P>Hi!</P><P>I've got the following problems with my project. My task is complete the NDSI index calculation in the Antartic region. A problem is some pixel values are much lower than should be.&nbsp;</P><P><BR /><span class="lia-inline-image-display-wrapper lia-image-align-center" image-alt="forum1.jpg" style="width: 400px;"><img src="https://community.esri.com/t5/image/serverpage/image-id/8034i9ADD54782F9A2670/image-size/medium?v=v2&amp;px=400" role="button" title="forum1.jpg" alt="forum1.jpg" /></span></P><P>&nbsp;</P><P><span class="lia-inline-image-display-wrapper lia-image-align-center" image-alt="NDSi (Blue = Thick snow, Green = Very think snow and ice, Red = no snow" style="width: 400px;"><img src="https://community.esri.com/t5/image/serverpage/image-id/8035i6F8A430089B15344/image-size/medium?v=v2&amp;px=400" role="button" title="forum2.jpg" alt="NDSi (Blue = Thick snow, Green = Very think snow and ice, Red = no snow" /><span class="lia-inline-image-caption" onclick="event.preventDefault();">NDSi (Blue = Thick snow, Green = Very think snow and ice, Red = no snow</span></span></P><P>&nbsp;</P><P><SPAN>I'm using ArcMap 10.4.1 verison. My data came from Landsat OLI 8 satellite (</SPAN><A href="https://earthexplorer.usgs.gov/" target="_blank" rel="noopener">https://earthexplorer.usgs.gov/</A><SPAN>) and the DEM data from REMA database (</SPAN><A href="https://www.pgc.umn.edu/data/rema/" target="_blank" rel="noopener">https://www.pgc.umn.edu/data/rema/</A><SPAN>)</SPAN></P><P>I've read about Topographic correction, but It didn't work succesfully. I didn't get higher pixel values behind the mountainous area.&nbsp;</P><P>I also tried this toolbox, but the ArcMap crashed while the last correction was running. That happend 3 times in the same point of the progress.(&nbsp;<A href="https://hub.arcgis.com/datasets/fd6ed990984945d5a9827418e67f26df" target="_blank" rel="noopener">https://hub.arcgis.com/datasets/fd6ed990984945d5a9827418e67f26df</A>&nbsp;)</P><P>&nbsp;</P><P>Thanks for the help!&nbsp;</P><LI-SPOILER>&nbsp;</LI-SPOILER><P>&nbsp;</P> Wed, 10 Mar 2021 11:26:08 GMT GeoKapor 2021-03-10T11:26:08Z https://community.esri.com/t5/arcmap-questions/topographic-correction-in-antarctica/m-p/1034846#M2117 <P>Hi!</P><P>I've got the following problems with my project. My task is complete the NDSI index calculation in the Antartic region. A problem is some pixel values are much lower than should be.&nbsp;</P><P><BR /><span class="lia-inline-image-display-wrapper lia-image-align-center" image-alt="forum1.jpg" style="width: 400px;"><img src="https://community.esri.com/t5/image/serverpage/image-id/8034i9ADD54782F9A2670/image-size/medium?v=v2&amp;px=400" role="button" title="forum1.jpg" alt="forum1.jpg" /></span></P><P>&nbsp;</P><P><span class="lia-inline-image-display-wrapper lia-image-align-center" image-alt="NDSi (Blue = Thick snow, Green = Very think snow and ice, Red = no snow" style="width: 400px;"><img src="https://community.esri.com/t5/image/serverpage/image-id/8035i6F8A430089B15344/image-size/medium?v=v2&amp;px=400" role="button" title="forum2.jpg" alt="NDSi (Blue = Thick snow, Green = Very think snow and ice, Red = no snow" /><span class="lia-inline-image-caption" onclick="event.preventDefault();">NDSi (Blue = Thick snow, Green = Very think snow and ice, Red = no snow</span></span></P><P>&nbsp;</P><P><SPAN>I'm using ArcMap 10.4.1 verison. My data came from Landsat OLI 8 satellite (</SPAN><A href="https://earthexplorer.usgs.gov/" target="_blank" rel="noopener">https://earthexplorer.usgs.gov/</A><SPAN>) and the DEM data from REMA database (</SPAN><A href="https://www.pgc.umn.edu/data/rema/" target="_blank" rel="noopener">https://www.pgc.umn.edu/data/rema/</A><SPAN>)</SPAN></P><P>I've read about Topographic correction, but It didn't work succesfully. I didn't get higher pixel values behind the mountainous area.&nbsp;</P><P>I also tried this toolbox, but the ArcMap crashed while the last correction was running. That happend 3 times in the same point of the progress.(&nbsp;<A href="https://hub.arcgis.com/datasets/fd6ed990984945d5a9827418e67f26df" target="_blank" rel="noopener">https://hub.arcgis.com/datasets/fd6ed990984945d5a9827418e67f26df</A>&nbsp;)</P><P>&nbsp;</P><P>Thanks for the help!&nbsp;</P><LI-SPOILER>&nbsp;</LI-SPOILER><P>&nbsp;</P> Wed, 10 Mar 2021 11:26:08 GMT https://community.esri.com/t5/arcmap-questions/topographic-correction-in-antarctica/m-p/1034846#M2117 GeoKapor 2021-03-10T11:26:08Z