Originally Posted by Hudson1
On an HD set, which are typically much larger than an SD set, both 480i and 480p look essentially the same to me. There seem to be greater differences between the sources than between the formats.
More important, I evaluated HD sets for a long time (as in weeks) and I had to get within about three feet of the screen to discern any real difference between 768p and 1080p (even on Blu-Ray or HD-DVD sources). What I found to almost always be the case is the difference between networks in digital broadcast quality. For instance, CBS I found to be likely the best and NBC always the worst despite both broadcasting in 1080i. In between were Fox and ABC, both broadcasting in 720P. For sports, the 720P format I found to often be best as it can take advantage of true 60HZ capability. 1080i is effectively only 30HZ since each line is drawn every other cycle.
As in most everything, it's more complex than the simple numbers themselves.
For example, 1080p is often recorded in 24 fps, to equalize with movie formats (which are actually double 24 fps, because they show each frame twice at 48 fps). If the pulldown isn't done well on a set, then 1080p 24 will look poorly.
Many new sets also run at 120 for Tv broadcast, which gives a denser image, which does look better.
If you can't see a difference between 480i and 480p, then something is wrong, because the difference IS quite noticeable at the propr distance, as noted on those charts.
I find that I agree the CBS has the best signal, but I can see the softer signals being broadcast by the 720p channels. That's obvious to me on my 61" set from about 6 feet. From my too far distance from the couch of 13 feet, I can't see the difference. Blu-Ray does look smoother, with better color though, because it's coming through the HDMI 1.3 inputs with "Deep Color" which no other HD or SD format offers now.
A set that converts 1080i to 1080p, again, gives a better signal, and the ones such as mine that also converts that to 120 Hz give an even better signal, particularly for fast moving video such as sports.