How long can an image be displayed before it permanently marks the screen? Im worried about channel tags in the top corner of the screen, Like E4 or skyone. The E4 logo is slighly translucent but skyone has an opaque logo. Does this mean I can watch E4 for longer? Also, im worried about nodding off and a channel finishing broadcasting and its stuck on the "This channel is off air" screen. Has anyone before damaged their screen in this way?