Hey my buddy has a budget model projection screen for his home theatre. Its rather blurry. Weve played with the focus mechanism. I know that thats just the downside of having a screen that big, but when i went into the setup features of the projector, the menus on the screen were like 45 times as sharp as any image or dvd we have ever seen on it. Why is this? Also is it necesary to dust off or wipe off the lense? The bullshitting salesman figures that "the heat is so intense it burns the dust off, no need to clean it ever" Yeah well take one look at it from the side and theres a bunch of crap on it. Will the glass scratch easily? lint free cloth?