diff --git a/scripts/color_relief.txt b/scripts/color_relief.txt
index ae51cd4..86d03ae 100644
--- a/scripts/color_relief.txt
+++ b/scripts/color_relief.txt
@@ -9,3 +9,4 @@
 80% 255 255 0
 90% 255 128 0
 100% 255 0 0
+nv 0 0 0 0
\ No newline at end of file
diff --git a/scripts/postprocess.sh b/scripts/postprocess.sh
index ad3a9a2..3607fc2 100755
--- a/scripts/postprocess.sh
+++ b/scripts/postprocess.sh
@@ -28,7 +28,7 @@ if hash gdaldem 2>/dev/null; then
 	for dem_product in ${dem_products[@]}; do
 		dem_path="odm_dem/""$dem_product"".tif"
 
-		gdaldem color-relief $dem_path $script_path/color_relief.txt "odm_dem/""$dem_product""_colored.tif"
+		gdaldem color-relief $dem_path $script_path/color_relief.txt "odm_dem/""$dem_product""_colored.tif" -alpha -co ALPHA=YES
 		gdaldem hillshade $dem_path "odm_dem/""$dem_product""_hillshade.tif" -z 1.0 -s 1.0 -az 315.0 -alt 45.0
 		python "$script_path/hsv_merge.py" "odm_dem/""$dem_product""_colored.tif" "odm_dem/""$dem_product""_hillshade.tif" "odm_dem/""$dem_product""_colored_hillshade.tif"
 	done