Q: I was visiting someone with a high definition TV. When they play back DVDs (normal ones, not Blu-ray), the images were letterboxed with black stripes on the top and bottom of the screen. What gives? I expect letterboxing on a square CRT but not on a widescreen HDTV. The TV plays HD broadcast channels in full screen mode just fine.
A: You’re certainly not alone in your observation, Michael. Lots of people complain about the black bars above and below or to the sides on their HDTVs. You can get rid of them, but it would be wrong. There are good reasons for them to be there.
In the case you cite, the bars above and below are there probably because the movie was filmed in CinemaScope. This is a cinema format that is wider than the 16:9 aspect ratio used on HDTVs. CinemaScope has an aspect ratio of 2.35:1 (which is the same as a 21.15:9 ratio). So how do you fit a wider image into the 16:9 screen?
Your choices are to trim the sides off the picture to make it fit the 16:9 screen, or simply stretch it vertically to fit. Both of these approaches eliminate the black bars of letterboxing, but the first cuts off some of the image and the second will distort it noticeably like making the actors look skinny. (I hate to see cars driving down the street on oval wheels. Many people find that once they start noticing these distortions, it’s so distracting that they can’t pay attention to the movie. It’s like all the times that the boom mike appeared in the shots in “Out of Africa”.)
That leaves doing the right thing: letterboxing. You get the full image in its normal aspect ratio so sizes are not distorted. Yes, you end up “not using” part of that big screen TV that you paid good money to buy, but I believe this will result in the best quality viewing experience. (If the black bars bother you too much, just drape curtains over the top and bottom portions, and pretend you’re in a movie theater.)
The other case where you get black bars to the sides occur when you are viewing a standard definition image (4:3 aspect ratio) on a wide screen. You can “zoom” the image to fill the screen — which cuts off content from the top and bottom — or stretch it to fill the screen which makes everyone look short and fat. (The last two hotels I stayed in had widescreen flat panel TVs in the room, but they were set to stretch SD content to fill the screen, and it made me nuts trying to watch it.) Once again, the best quality image will be the one with the black bars on the sides.