Problems with fogfilter

gistfile1.as

var fogMaterial:ColorMaterial = new ColorMaterial(0xBCC687);			
var fog:FogFilter = new FogFilter({ minZ:100,
				    maxZ:600,
				    subdivisions:20,
				    material:fogMaterial } );

var filters:Array = [fog];
			
var renderer:BasicRenderer = new BasicRenderer();
renderer.filters = filters;

backView           = new View3D();
backView.scene     = new Scene3D();;
backView.camera    = camera;
backView.renderer  = renderer;
backView.x         = 0;
backView.y         = 0;
backView.blendMode = BlendMode.LAYER;

frontView          = new View3D();
frontView.scene    = new Scene3D();
frontView.camera   = camera;
frontView.renderer = renderer;
frontView.x        = 0;
frontView.y        = 0;