diff --git a/tools/mkloop.sh b/tools/mkloop.sh
index 95a86f1..0aa5e4a 100755
--- a/tools/mkloop.sh
+++ b/tools/mkloop.sh
@@ -34,7 +34,7 @@ do
 	err=$?
 	if [ $err != 0 ] ; then
 		echo "$SEQNAME fail $frame" >> WS/log
-		mogrify -colorspace gray -blur 5x5 $img
+		mogrify -colorspace gray -blur 5x5 -colors 16 $img
 		visual_sleep "render fail" 12
 		continue
 	fi