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1080I vs. 720P for Sports

kmantapeman
11-21-2005, 06:02 PM
When receiving 1080I it seems the Panny which converts to 720P
has a problem? The whites in HD seem to have a trail on them. Does anyone know if the converter in the tv is not up to par for the conversion?

kmantapeman
11-27-2005, 11:16 AM
In reading the threads about both formats, ESPN,FOX,ABC shoot in 720P and NBC,TNT,CBS use 1080I and I have to say 720 is far superior
and vibrant. 1080I has a trail of white in it when the action moves to fast. The interlace can't cath up quick enough. Please any comments on this would be helpful. Does anyone else see and know why it is a much different picture? Also my Panasonic PT50LC14 Rear Projection
converts everything to 720P, can this be the problem that the converter is not up to par or is that 720P for sports is just better? Thanks

rbinck
11-27-2005, 11:57 AM
There is a problem here in Houston with the NBC, CBS and PBS stations broadcasting subchannels that will cause fast motion to become blocky due to overcompression. Since the 720p requires up to 15Mbps and 1080i requires up to 19.4 Mbps, the 1080i is more effected by the syphoning off of bandwidth to the subchannels.

As far as your white trailing, I've never heard of, or seen, that particular situation and I would be hesitant to blame your set for this. Different manufacturers use different technologies for converting 1080i to 720p and I must say I don't know the Panasonic method.

Overall, I would say that you are correct in saying the 720p is better for fast motion than the 1080i, but the reason is not resolution or interlacing but frame rate. The 720p is at 60fps and the 1080i is at 30fps. Interlacing will have very little to do with the fast motion, it is primarily frame rate differences.

In deciding what TV set to buy, it is good to remember that the only 720p/60fps programming that is shot in 720p/60fps is a few hours a week on FOX, ABC and ESPN live sports programming.

Edit: I merged your earlier post which ask about the white issue to get both posts adressed here.

JimM
11-27-2005, 03:49 PM
I'm certainly no expert, but for what it's worth ... while watching the Chiefs game today (CBS 1080i), I was flipping over to the Bears game (Fox 720p) between plays. Both channels were from my OTA antenna coming from the Quad cities. To my eyes, the Bears picture looked good, but the Chiefs picture was amazing. When my 17 year old son walked in the room and started watching, unprompted, he voiced the same opinion on the difference in picture quality.

siccivic420
11-28-2005, 02:07 PM
I have a 1080i mitsu. hd crt 55'' and had a 720p 61'' samsung dlp and can tell you that watching fox 720p sports on a 1080i tv isn't near as good as cbs 1080i sports on the same tv.espn and abc were better but i think they have better hd camera's then fox.But on a 720p tv sports look good on fox and cbs, but great espn and abc.I want to get a 1080p hdtv so i can switch between the formats and have it look good on it.To bad dlp has the whole whobulation thing and the sony sxrd lcos and jvc 1080p lcos don't accept 1080p for sony ps3 video games.

Mattd46612
11-28-2005, 10:21 PM
Wish I had the option of 720P, but unfortunately my 51HC85 only does 540p or 1080i. But the 1080i looked great for monday night football, just wish i had 720p to look for myself.

puck71
11-29-2005, 06:59 AM
I'm certainly no expert, but for what it's worth ... while watching the Chiefs game today (CBS 1080i), I was flipping over to the Bears game (Fox 720p) between plays. Both channels were from my OTA antenna coming from the Quad cities. To my eyes, the Bears picture looked good, but the Chiefs picture was amazing. When my 17 year old son walked in the room and started watching, unprompted, he voiced the same opinion on the difference in picture quality. The picture itself will probably be "clearer" on 1080i than 720p but the advantage of 720p becomes apparent when there's fast motion, like when the cameras pan relatively quickly. On 1080i this will pixelate more noticeably than 720p. 1080i will "look" clearer on a still shot and on low motion video, but when things start moving faster 720p becomes (in my opinion) the overall winner.

Plus there are always other variables like quality of equipment used through the whole pipeline, etc. (CBS cameras may be better than FOX and so on)

kmantapeman
11-29-2005, 06:49 PM
Thanks for the frame rate issue. About the white trail it is on white uniforms and anything white, it has sort of a white pixel trail but not so much of a blocky but a trail hard to explain ,it is very hard to watch from 720P when there is no problem with pixel trails. Thanks

rbinck
11-30-2005, 08:29 AM
Sounds like it could be overprocessing of the video. Try reducing the sharpness and turning all noise filters off and see if the condition is still there.

zombie450
11-30-2005, 04:01 PM
To bad dlp has the whole whobulation thing and the sony sxrd lcos and jvc 1080p lcos don't accept 1080p for sony ps3 video games.

What is "whobulation " on the new DLP's ? Is it different than the old models?

rbinck
11-30-2005, 04:28 PM
Yes it is different. It is a technique developed by HP and then licenced to TI to allow the 960x1080 DLP chip to double the horizontal pixels to yeild 1920x1080 total resolution. It requires the use of the newest TI micromirror chips that can operate at 120Hz.

And it is wobbulation.

maicaw
11-30-2005, 06:02 PM
. It requires the use of the newest TI micromirror chips that can operate at 120Hz.....And it is wobbulation.has anyone seen a spec ("MTBF"-wise)?for how long those million or so mirrors can wobble at 120~ before a couple of them quit working?

rbinck
12-01-2005, 09:43 AM
The first micromirror chips were developed for use in telecom switches to give infinate bandwidth to the switch. TV applications came later. The MTBF is very high, but I don't recall the number. The MTBF of the120~ are not different than the 60~ as they are newer designs. Check www.dlp.com (http://www.dlp.com/)

rbinck
12-02-2005, 08:47 PM
Thanks for the replys. I watched TNT NBA b-ball last night and the tight shots were terrible, alot of boxy pixels when they moved but the game camera (wide shot was ok) also when I watch the highlights on ESPN of CBS,NBC,TNT the playback is fine no trailing is it they are recording on 720p HD VTR and playing back at 720P?? or is it ESPN's transmission is just perfect? kmantapeman

I can't say for sure. ESPN could be getting raw feeds that have not been through nearly the transmission paths that a game you see on your TV has gone through. I've never seen the problem of white trails.