that projector is a native 4:3 image, so you will not be able to get rid of the extra light, my projector is also a native 4:3 and when in 16:9 mode i get the extra light also..thhere is nothing you can do abouut that.. the only thing you may be able to do is when you buy your projector, and you want to have 16:9 then make sure you get a projector with a native 16:9 image.

hope this helps.