Michael St. Clair,
Here' a quote from the committee's resolution introduction hyperlinked above: "In the case of an interlaced scanning system, for vertical resolution under motion, the picture will take on the characteristics of a progressively scanned system with half the number of scanning lines (i.e., vertical resolution of 1080I becomes 540P under motion)."
Getting into upsampled (or plain) DVDs vs. HDTV is often discussed here. IMO, the key factor is the original method of capturing images. A 1080X1920 camera or telecine scanner can record those resolutions, and later filtering/viewing them may produce the results shown above. An NTSC DVD may be prefiltered to something less than 720X480 and see similar reductions, percent-wise, when displayed.
My suspicion is that you have to start out with displays capable of nearly the full 1080i ATSC spec in order to achieve what the FCC's committee saw. Seems to me that if you 'dumb down' set resolution capabilities to match what's displayed in the results above, images would really suffer. That is, to obtain the 800 and 400 (static, dynamic) vertical resolution the committee measured for 1080i, you have to start out with displays approximating 1080 scan lines or the equivalent. Remember, sets filter image signals before displaying them. And vertical resolution is what can be resolved by displaying image signals on these scan lines, not the scan lines themselves. And of course many sets lack the bandwidth or basic display technology to handle the higher horizontal resolutions measured by the committee.
There's a new Samsung 16:9 LCD computer monitor now available that matches the 1080i ATSC spec perfectly. Signals can be piped into it via DVI, which bypasses any analog conversions. So, assuming you could track down a full 1080i or 1080p source, what happens to a presumably unfiltered HDTV image on the Samsung screen? -- John
[This message has been edited by John Mason (edited 08-21-2001).]