This was discussed at the Home Theater Forum back in '97:
It's just a slight compromise in the way the films were formatted for home video. People have this misconception that every movie that you see in widescreen on DVD or laserdisc is the perfect presentation and exactly duplicates down to the centimeter what it looked like on the big screen.
That's not always true. Some film directors have agreed on a happy medium, wherein the picture is shown as acurately as possible while not going overboard with letterboxing the image.
Look at the scene in ANH:SE when R2 and 3PO are outside the cantina, and 3PO says "I don't like the looks of this." In the cinema, we clearly saw a stormtropper climbing off a dewback on the left side of the screen. On the 1997 SE widescreen laserdisc, only the dewback could be seen. The trooper had been cropped off. But now on the DVD, you can see him again. So, the Star Wars DVDs are actually
more widescreen, if you will, than the 97 widescreen release.
Transferring widescreen films to home video is a constant process of adjustment. Look at the first LD or DVD releases of
Heat. The black bar at the bottom of the screen is incredibly thick, and I have yet to hear any Michael Mann fans bitch about it.
