diff --git a/lib/torque/renderer/ball.js b/lib/torque/renderer/ball.js
index bc1bfc5..e8777eb 100644
--- a/lib/torque/renderer/ball.js
+++ b/lib/torque/renderer/ball.js
@@ -153,10 +153,7 @@ BallRenderer.prototype = {
     createArray: function(){
     	return new Uint8ClampedArray(this.size * 4);
     },
-    isopleth: function(factor){
-    	var skip = false;
-    	if(!(factor>0)) factor = 1;
-    	this.isoplethLayer = this.createArray();
+    isopleth: function(){
     	for (var i = 0, len = this.contourLayer.length; i<len; i+=4){
     		var alpha = this.contourLayer[i + 3];
     		if (alpha > 0 && alpha < 255){