Hi there, I recently had a bulb change for my domino 20 and upon re-installing my projector picture is great apart from some rainbow coloured patches/smudges up the right hand side and top left hand corner. They are only really visible on brightly coloured pitches, most notably on a plain white still screen. Could this be dust or fingerprints on the lenses or new lamp when it was replaced? anyone have any suggestions or similar problems? Kind regards and thank you for your time