At 12:09 PM -0500 5/19/05, Doug McDonald wrote: >Craig Birkmaier wrote: > >> >> What is important is not the source resolution but delivering a >> sharp, high quality picture to the average display. >> > >No, Craig, it's not to the AVERAGE display, it's to the BEST >display. > You've got to be kidding. This is a digital television system for the masses; perhaps a whole lot more. But one thing it ain't is a play toy for videophiles and the folks who hang out at the AVS forum. According to Hollywood, "The Best" is 4K x 2K on a gigantic screen. Is this what you are expecting from DTV? Optimizing for "The Best" is an elusive target. With respect to the ATSC standard was it at its best in 1997? In 2000? In 2004? Or will it be 2007? 2010? 2020? Here's a big hint. Every day that passes, the ATSC standard becomes less relevant. MPEG-2 is no longer "The Best" compression technology. 8-VSB never was "The Best" modulation technology. And broadcasters are still doing "Their Best" to ignore the mandate to move to DTV, favoring instead to stay with "The Best" we could do half a century ago. NTSC is at it's best on a 19" screen viewed at seven picture heights. Being the BEST is a continuously moving target. The trend-line is always UP, perhaps to counterbalance "Good Enough", which keeps trending down. Those who can afford "The Best" will always seek something better than what the average viewer expects. The truth is that today's off-the-shelf 65" HD capable displays deliver better picture quality than the videophile systems of a decade ago. Yet people are still spending six figures on state-of-the-art home theater systems, because they want "The Best." By know you should understand that for DTV, big numbers DO NOT mean that something is "The Best." There are too many variables in terms of original source quality and what happens to that source as is moves from creation to emission. And numerology, both in terms of acquisition and display rasters can be highly misleading. What matters is delivering a sharp picture on the screen at the designed viewing distance. Large displays that need more samples to deliver the HD experience can do so with proper re-sampling. We have a new generation of 1080@60P displays hitting the market, yet 1080@60P is not even a meaningful format for acquisition or emission today. What these displays need is high quality source to convert to 1080@60P - Good 720P will equal or exceed the quality of 1080i source on these displays in most cases. It is the integrity of the samples, not the number or samples that matter. And just for the record, the average HD display size today is near the lower end of the range of screen sizes that are well served with 720P. The growing interest in LCD panels is likely to cause the average screen size to decrease rather than increase. And one more thing. I was in Circuit City yesterday cruising the HD displays. If you were to ask people what size set had "The Best" picture quality, the answer would be the ones that are smaller than 40 inch. Why? Because the demo loop was so poor that on the big screens you could see all kinds of compression garbage. So be careful when you are asking for a system to be optimized for "The Best." > >720p is adequate for ANY size display if you sit far enough back! DUH. A 13" NTSC set is as sharp as most HD displays. You are a scientist Mr. McDonald. You understand basic math and physics. Therefore you should be able to figure out that there is a simple relationship between screen size, viewing distance and resolution requirements. Two things are important: 1. That you cannot see evidence of the raster (one of the best reasons to be rid of interlace). 2. That the display be capable of delivering details in the range of 22-30 cycles per degree of the viewing field, which is what the human visual system needs for the perception of a sharp picture. Obviously good contrast and good MTF performance go hand in hand. Do the math Mr. McDonald, and you will find that 720P is adequate for screens approaching 100" diagonal at a viewing distance of 3.3 picture heights. > >I'd say that for most people 720p is great for 40 inch displays >like I own, and OK at 60 inches. But at anyting over 50 inches, >you really clearly will be happier with better .... unless >the incoming sigal is fuzzy, of course. Do the math. By the way, the incoming signals are a big part of the problem. That "FUZZ" is trashed samples that have been over compressed. Regards Craig ---------------------------------------------------------------------- You can UNSUBSCRIBE from the OpenDTV list in two ways: - Using the UNSUBSCRIBE command in your user configuration settings at FreeLists.org - By sending a message to: opendtv-request@xxxxxxxxxxxxx with the word unsubscribe in the subject line.