Quote:
Originally Posted by gazzae
I have a Sharp Aquos can't remember the model.
Will give it a shot later tonight. Whats the difference between P and I?
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From CNET.COM
1080i - 1080 interlaced; one of two formats designated as high-definition television in the ATSC DTV standard, with 1,080 vertical pixels by 1,920 horizontal pixels. The i stands for interlaced, as opposed to progressive scanning, used in the second HDTV standard, 720p. Contrary to myth, 1080i is not superior to 720p; 1080i has more scanning lines but also suffers the disadvantages of interlaced scanning.
720p - 720 progressive. One of two currently used formats designated as high-definition television in the ATSC DTV standard, this technology comprises 720 vertical pixels and 1,280 horizontal pixels. The p stands for progressive, as opposed to interlaced, scanning, which is used in the other accepted HDTV standard, known as 1080i. Contrary to myth, 720p is not inferior to 1080i; 720p has fewer lines but also has the advantages of progressive scanning and a constant vertical resolution of 720 lines, making it better able to handle motion
http://techdigs.net/content/view/53/42/
Progressive scan means the lines that make up the TV picture are displayed all at once in sequence. HDTVs are capable of at least 1280x720p ('p' for progressive scan). While they can also accept an interlaced signal, they natively display progressive scan video.
Progressive scan DVD players are capable of 720x480p, and the newer upscaling DVD players and high def DVD players are capable of up to 1080p depending on the model (see the
TechDigs.net article Want Better DVD Movies? Buy an Upconverting Player!).
Without getting into the gory details, the interlaced method was originally used because CRT technology in early TVs wasn't fast enough to keep up with a progressive scan of approximately 480 lines. It could, however, keep up with 240 lines. Therefore, standard U.S. TV broadcasts first send the even 240 lines, and then the odd 240 lines.
The problem with interlacing technology is this alternating line drawing tends to cause the eyes to see a flicker. Unfortunately, interlacing reared its ugly head again in the 1990s when established HDTV standards included both 720p and 1080i options. Some broadcast networks use 1280x720p (720 lines progressively displayed) and some use 1920x1080i (540 even lines drawn, then 540 odd lines drawn). As of 2006, no U.S. broadcast network uses 1080p, or 'full HD' (1920x1080p).
The problem with 1080i is that despite having more total lines, it generally doesn't look as good as 720p. This is especially true for high-motion video such as sports. If you have a large (over 46") HDTV hooked up properly and want to see an example of this, watch a punt return on HDTV NBC Sunday Night Football, and then watch a punt return on HDTV Monday Night ESPN Football. The difference is significant. With far less aliasing (visible chunky pixels), ESPN's 1280x720p looks substantially better than NBC's 1920x1080i. While some of this may be due to the compression used by NBC or the cable outlet, most of it is due to interlacing.