I'm looking for a Fisheye Converter for my Nikon D40 the lens is 18-55mm. I've been looking around locally for a Fisheye converter. I was wondering what I need to get something like these pictures here. Not sure if I need a Fisheye converter, or a Fisheye Filter. I saw a fisheyey filter. I'm not really sure how it works. I don't wanna spend a lot for an actual Nikon Fisheye Lens.