High Definition Question

[KidViciou$]

why are set's advertised as being able to do 720P and 1080i when they really downstream it to 540P or something similar?

is there anything out there that would do at least 720P natively?

 

[kami]

WHat sets are you speaking of? Toshiba's upconvert anything below 540p TO 540p, but 720p material is converted to 1080i

As for sets that do 720p natively, very few. I can't recall any off the top of my head. I think some Plasma's have a native resolution of 720p.

 

[TechnoKid]

Some LCD and LCoS projectors can display 720p natively. It's not that the screen or chip doesn't have enough pixels per say, but perhaps the video processor can't handle the bandwith of 720P. This would be a wrong assumption if 1080i infact has more bandwidth than 720P.

 

[KidViciou$]

for the record, im not an AV guy. i was looking at this

Hitachi F500 @ sears

Display Format 540p


That made me think it can do a max of 540P and everything is either upconverted or downconverted to that.


So regular projection TV's do 1080? Why don't they do 720P?

I can understand projectors would have a lower capability, i'm using my cousin's HD projector and it still looks good, but i'm in the market for a projection tv

 

[TechnoKid]

Originally posted by: KidViciou$
for the record, im not an AV guy. i was looking at this

Hitachi F500 @ sears

Display Format 540p


That made me think it can do a max of 540P and everything is either upconverted or downconverted to that.


So regular projection TV's do 1080? Why don't they do 720P?

I can understand projectors would have a lower capability, i'm using my cousin's HD projector and it still looks good, but i'm in the market for a projection tv

I believe all that "540P" spec means is that it can convert incoming 540i siganls to progressive, its under "display enhancements". Sorta like a built in progressive scanner/line doubler on a dvd player, except the TV has one too. This would be useful for say, a computer hookup, but not motion film, unless the progressive converter does 2:3 pulldown. Its horizontal res is 1280 lines.

 

[amnesiac]

edit: I think I spouted crap; momentarily retracted until I confirm my statements

 

[KidViciou$]

ok, cool. thanks for the explanation

 

[Amused]

Yep, all HDTVs can do 1080i or at least 720p. If not, it is called an E(enhanced)DTV.

Hitachi UPconverts all SD content to 540p. But HD content is shown in 1080i (including 720p material which is upconverted to 1080i).

I have a Hitachi HDTV and love it.

 

[KidViciou$]

i thought that 720P is better for movement than 1080i?

 

[Ameesh]

Originally posted by: KidViciou$
why are set's advertised as being able to do 720P and 1080i when they really downstream it to 540P or something similar?

is there anything out there that would do at least 720P natively?

my samsung DLP does 720P nativly

 

[KidViciou$]

i hear Samsungs are the best projection tv's

 

[GRIFFIN1]

Saying that 720P is upconverted to 1080i isn't really true. 1080i is interlaced so it only shows 540 lines with each frame. 720P shows 720 lines with each frame, so it's actually better than 1080i.

 

[TechnoKid]

Originally posted by: GRIFFIN1
Saying that 720P is upconverted to 1080i isn't really true. 1080i is interlaced so it only shows 540 lines with each frame. 720P shows 720 lines with each frame, so it's actually better than 1080i.

From my understanding, in 1080i mode, the video processor splits a "frame" into two scans, one for the odds and one for the evens. It does so at 60mhz. Yes, it does only display 540 lines at a time (but 1080 total in 1/30 of a sec), but these combine to make the final complete frame. 1080i mode is only "half" the frame so to speak at a time.

Basically, as you stated, 720p actually refreshes twice as often per each frame compared to 1080i. For the time it takes 1080i to show a complete frame, 720p has shown it twice. This creates what I percieve to be a higher looking resolution. 720p is perhaps equivalent to 1440i because in the time it took for 1080i to diaplay all 1080 lines, the 720p has effectively shown 1440 line already.

I can't wait till 1080p makes it to the consumer level. They already have used it for movies in the theater that were brodcasted digitally (I think one of the star wars was like this).

 

[Apex]

Though 1080i is interlaced, it's 1920x1080. 720p is 1280x720. Just considering the vertical res & refresh gives you only 2/3 of the picture. I'd much rather a display that can fully resolve 1080i than 720p.

 

[BigToque]

When will 1080p come along?

 

[bcterps]

Originally posted by: Stefan
When will 1080p come along?

I believe some of the new LCoS sets coming out can display 1080p.

My Panny RP LCDTV displays 720p natively.

 

[Apex]

There are very few sets that can fully resolve 1080p now.

Toshiba 57HLX82 - $6k or so
Toshiba 57HL83 & 65HL83 (not released yet) - $5k - $7k
Mitsubishi Alpha 82 - $20k
JVC DLA-QX1 (2048x1536 native) - $225k plus lens... and waiting list is getting long
Sony Qualia 004 - $25k
Christie Digital CP2000H & CP2000i - $250k or so
Barco D-Cine Premiere DP100 - $200k+ depending on configuration
Digital Projections Lightning 35HD - $150k

I'm probably missing a bunch.

 

[MazerRackham]

Is there a good website that explains in detail all the HDTV formats and stuff? I need to read up in this area...

 

[Wag]

I have a Panasonic DT-M3050W 30" 16:9 CRT that can display 720p natively. I actually prefer it over 1080i, and watch everything in 720p.