On Wed, Dec 31, 2008 at 2:55 PM, David James <bigdadd...@gmail.com> wrote: > I've never quite understood why a 1080p tv won't do 1920 x 1080.
From what I've read: In theory, a TV is just a display monitor with a built-in tuner. But in practice, there can be hidden differences in what the tuning and signal processing electronics can handle. In ATSC, there's no definition for 1080p (1920x1080 progressive). 1080i (interlaced) is the highest they go. So a TV claiming 1080p is claiming something that isn't defined in the TV standards. In some cases, apparently this is a pure marketing gimmick: They're referring to the fact the actual display panel always draws all lines, so it's "progressive", even though the signal input electronics don't have the capability of processing a 1080p signal. I imagine some TVs actually can accept a 1920x1080 progressive signal from a computer. The specs should say exactly what modes it supports. If they don't, don't count on them. There's also all the other specs that might matter, like brightness, contrast ratio, pixel refresh speed, pixel pitch, and so on. I know it used to be that monitors intended for TV were much inferior to monitors intended for use with a computer in this regard. So check those specs carefully. Caveat emptor. (ATSC = Advanced Television Standards Committee, which defined most of the digital TV and high-def TV stuff for the US.) (Progressive/interlace: Progressive means drawing every pixel line for every vertical refresh. Interlaced draws all the even lines in one refresh, all the odd lines the next. In the days of the original NTSC tube TVs, this meant less bandwidth (you only had to send half the lines per unit of time), and less expensive electronics, since the beam sweeping the tube didn't have to move as fast. With digital flat panels, there's no beam sweep, so it's always doing *something* for all pixels. But if the signal feeding it is interlace, there's no data for half the lines, so it either uses the last field, or fills in black, or interpolates, or otherwise makes up data.) -- Ben ~ Finally, powerful endpoint security that ISN'T a resource hog! ~ ~ <http://www.sunbeltsoftware.com/Business/VIPRE-Enterprise/> ~