diff --git a/ImageOptim.sh b/ImageOptim.sh
index 543d62d61..dd5332d91 100755
--- a/ImageOptim.sh
+++ b/ImageOptim.sh
@@ -10,7 +10,7 @@ if [ "$CONFIGURATION" == "Debug" ]; then
     exit 0
 fi
 
-CONVERT=/opt/local/bin/convert
+CONVERT=$(which convert)
 CONVERTFILTER="-sharpen 1x0.0 -filter Catrom"
 OPTIPNG=/opt/local/bin/optipng
 CMDS="${CONVERT} ${OPTIPNG}"
@@ -78,4 +78,4 @@ for PNG in $PNGS; do
 done
 
 # make sure we dont over-optimize
-touch $DIR/optimized
\ No newline at end of file
+touch $DIR/optimized