diff --git a/pack-set b/pack-set
index 7a187cb..c9bc138 100755
--- a/pack-set
+++ b/pack-set
@@ -11,9 +11,11 @@ for INFILE in "$@"
 do
     echo "$INFILE"
 
-    COMMON="$OPTS --hdr --exposure=-2.5 --peak=141 --fps=60000/1001"
+    #COMMON="$OPTS --hdr --exposure=-2.5 --peak=141 --fps=60000/1001"
+    COMMON="$OPTS --hdr --exposure=-2 --peak=500 --fps=60000/1001"
     SPEED_SMALL="veryslow"
-    SPEED_LARGE="medium"
+    #SPEED_LARGE="medium"
+    SPEED_LARGE="veryslow"
 
     SMALL="$COMMON --size=4m --preset=$SPEED_SMALL"
     LARGE="$COMMON --size=25m --preset=$SPEED_LARGE"
diff --git a/pack-vid b/pack-vid
index 7bcc76f..4c84e66 100755
--- a/pack-vid
+++ b/pack-vid
@@ -27,6 +27,7 @@ $options = [
     'size' => $maxBytes,
     'quality' => 1.0,
     'hdr' => false,
+    'dither' => false,
 ];
 
 while ( count( $args ) > 0 && substr( $args[0], 0, 2 ) == '--' ) {
@@ -53,7 +54,8 @@ if ( count ( $args ) < 2 ) {
         "  --fps=n        frame rate limit\n" .
         "  --size=n       target file size in bytes (default 3.5M)\n" .
         "  --quality=n    fraction of base bitrate to break on (deafult 0.75)\n" .
-        "  --hdr          force HDR input processing on\n"
+        "  --hdr          force HDR input processing on\n" .
+        "  --dither       enable dithering in 8-bit downconversion\n"
     );
 }
 [ $src, $dest ] = $args;
@@ -267,8 +269,13 @@ function convert( $src, $dest, $options ) {
             $filters[] = "exposure=$exposure";
         }
         $filters[] = "tonemap=hable:peak=$peak:desat=0.0";
-        $filters[] = "zscale=t=bt709:p=bt709:m=bt709:r=full";
-        $filters[] = "vibrance=0.0625";
+        if ( $options['dither'] ) {
+            $dither = ":dither=ordered";
+        } else {
+            $dither = "";
+        }
+        $filters[] = "zscale=t=bt709:p=bt709:m=bt709:r=full$dither";
+        $filters[] = "vibrance=0.2";
     }
     $filters[] = "format=yuv420p";
     if ( $crop ) {