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HDTV source resolutions
If you read those three axioms closely, you'll see that source is everything with HDTV. Or, as some unknown wag once said, "Garbage in, garbage out." There are two main HD resolutions in use today by HD broadcasters and other sources: 1080i and 720p. One is not necessarily better than the other; 1080i has more lines and pixels, but 720p is a progressive-scan format that should deliver a smoother image that stays sharper during motion. Another format is also becoming better known: 1080p, which combines the superior resolution of 1080i with the progressive-scan smoothness of 720p. True 1080p content is extremely scarce, however, and none of the major networks have announced 1080p broadcasts.
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2. Why 1080p is theoretically better than 1080i
1080i, the former king of the HDTV hill, actually boasts an identical 1,920x1,080 resolution but conveys the images in an interlaced format (the i in 1080i). In a tube-based television, otherwise known as a CRT, 1080i sources get "painted" on the screen sequentially: the odd-numbered lines of resolution appear on your screen first, followed by the even-numbered lines--all within 1/30 of a second. Progressive-scan formats such as 480p, 720p, and 1080p convey all of the lines of resolution sequentially in a single pass, which makes for a smoother, cleaner image, especially with sports and other motion-intensive content. As opposed to tubes, microdisplays (DLP, LCoS, and LCD rear-projection) and other fixed-pixel TVs, including plasma and LCD flat-panel, are inherently progressive in nature, so when the incoming source is interlaced, as 1080i is, they convert it to progressive scan for display.
3. What content is available in 1080p?
Really, nothing at this point. Today's high-def broadcasts are done in either 1080i or 720p, and there's little or no chance they'll jump to 1080p any time soon because of bandwidth issues. Meanwhile, some newly announced DVD players from Denon and NeuNeo (who?) are claiming to upconvert standard DVD movies to 1080p resolution, but that's a far cry from native high-def content. More promising is the post-DVD future. There's been a lot of chatter over whether the new breed of high-def movie players, Blu-ray or HD-DVD, as well as the upcoming Sony PlayStation 3, will output in 1080p. Allegedly, they will, but those players and recorders will be very expensive at first (more than $1,000), and they probably won't hit more modest price levels until 2007 or even 2008. The PS3, on the other hand, is designed to be more of a mainstream product; we hope that means a price tag in the neighborhood of $500. It's unclear, however, exactly what it will output in 1080p--games, Blu-ray movies, or both--or neither.
Senior Editor David Katzmaier, reports that the extra sharpness afforded by the 1080p televisions he's seen is noticeable only when watching 1080i sources on a larger screen.