On my HL-S6187W im getting some type of ghost image or a light shade of grey when the screen is all black. i cant see these palm-sized circles when anything else but black is on the screen. At first i thought it was some type of finger prints but unfortunity it wasnt. ive tried taking a picture but its hard to see. about to call a tech person but dont have a warranty on this set but i do on my first dlp (the original). what could this be and better yet how can i fix it. thanks in advance to whoever can help.