Why Don All TV Programs Fill the Whole HDTV Screen?
Unless you use upscaling technology (see question #11), SDTV displays at its native 4:3 aspect ratio on a 16:9 HDTV display. The result is a picture that fills the screen from top to bottom, but that shows a black area on both the left and right sides of the picture. That happens because the TV set normally scales the image to fill the pixel space on the display as best it can without changing the aspect ratio. Essentially, because SDTV is a narrowscreen medium and HDTV is a widescreen technology, SDTV broadcasts result in screens that are incompletely filled.
