Этот плагин значительно все упростит: http://www.corel.com/servlet/Satellite?pagename=uk/Layout&c=Product_C1&cid=1152105061771&lc=en
Hair, smoke, shadows, water, transparencies and any blurred or out-of-focus edges can now be masked with incredible precision, speeding up the entire design process. Plus, Corel KnockOut 2 is an ideal plug-in for Adobe® Photoshop®, Corel PHOTO-PAINT® or Corel® Painter™ 8, so it fits seamlessly into your workflow.