I got a hold of one of these super awesome lens attachments... the HD2 opteka fisheye. It is super awesome. It did not work with my 50 mm lens, but works wonderfully with my 17-85mm lens (using a ring adapter). The effect would be super awesome on a 17-55mm lens. The reason there is so much black on the photo is because the 17-85mm lens is 67mm ring size and the opteka fisheye is a 52. The opteka comes with a 58mm adapter ring. It also has a built in macro lens that gets super, super close to things. It's great.