What its EDTV and HDTV??
Master
Standard TV has 525 lines of interlaced video. Interlacing means that the video (which is split into 2 fields) gets shown alternately. Of the 525 lines only 480 have a video signal. That’s the 480i you see floating around in all the EDTV vs HDTV specifications.While standard TV has worked well for years TV sets have gotten bigger and the deficiencies of SD (standard TV) have become magnified. There's no question that in EDTV vs HDTV the HDTV (for now) is the ultimate in PQ (picture quality).
EDTV has the same 480 lines as SD, but they are progressive scan. SD uses 480i (interlaced) and EDTV uses 480p (progressive scan). DVD players uses progressive scan to display PQ and EDTVs do a great job of displaying them.Progressive scanning means that instead of splitting the signal into two fields and showing half the lines at a time, all 480 lines of video are shown at once. That’s one of the reasons why DVDs look so sharp on your SD TV.
An HDTV needs to re-process the signal before it can display it to you. As said before a DVD player's natural resolution matches that of the EDTV format. Perhaps the most important factor is the viewing distance. How good the PQ is has a lot to do with seating distance. It's a fact that if you sit 8 feet or more from you TV you won't be able to tell the difference in sharpness between a 42-inch EDTV and a 42-inch HDTV side by side.If you get close to an EDTV say 6 feet or less you start to see the screen door effect (SDE). That's when you start to see the actual pixels on the EDTV.
If you watch sports, the Discovery channel and other channels that will eventually swing into HD programming and you sit close to you TV then HDTV may be for you. At this point in time EDTV vs HDTV depends mostly upon your viewing distance. If you have the bucks or you sit close to you TV than the EDTV vs HDTV choice is HDTV.
HDTV has an impressive 720 progressive scanning (1280x720 pixels) or 1080
interlaced (1920x1090 pixels) lines. Thus, it easily meets the requirement of
high definition broadcasts. EDTV, on the other hand, displays pictures at 480
progressive scan (640x480 pixels), which is the the highest resolution available
on DVD. In fact, EDTV is considered optimized for the DVD format. However, this
puts a severe limit on EDTV, which is simply not able to display higher
resolution HD content.