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I've had HDTV for 1 day now. I'm using a 46" 1080p 120Hz LCD TV on DirecTV with an HR22 HD DVR and a 120Hz HDMI cable. Here's what I've noticed. Please tell me if all this is normal:


Some 720p programs look better than 1080i. Is this because nothing's actually broadcast in 1080p, and there must be some sort of conversion to display 1080i on a 1080p TV? I thought maybe 720p was sent progressive scan, received progressive scan, and displayed in progressive scan, hence no conversion and a picture as good or sometimes better than 1080i.
 

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Both resolutions need to be upscaled to your display's native 1080p resolutions. There are a couple ways of doing each, depends on what the manufacturer of your TV is doing. You may find some answers in the LCD Flat Panel forum.


On a side note, no such thing as a 120Hz HDMI cable, marketing BS. The signal you're getting is 60 Hz and the doubling is done internal to the television.
 

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Quote:
Originally Posted by bighoopla /forum/post/15465133


I've had HDTV for 1 day now. I'm using a 46" 1080p 120Hz LCD TV on DirecTV with an HR22 HD DVR and a 120Hz HDMI cable. Here's what I've noticed. Please tell me if all this is normal:


Some 720p programs look better than 1080i. Is this because nothing's actually broadcast in 1080p, and there must be some sort of conversion to display 1080i on a 1080p TV? I thought maybe 720p was sent progressive scan, received progressive scan, and displayed in progressive scan, hence no conversion and a picture as good or sometimes better than 1080i.

When you first go to this site ( www.avsforum.com ) before you click on the "Forums" tab, they are right now running an article about this very subject. Bottom line: 720p is better for fast action sports. 1080i CAN be slightly better for dramas and film based 24 fps material. But, then again it can depend alot on your source provider (cable, satelite, etc) and how much they compress the signals.
 

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720P programs will look better on a 720p unit then on a 1080p unit since no invention of the additional 1 million pixels has to be performed. However, only ABC , FOX and ESPN-HD broadcast HD programs in 720p. With the exception of some PBS stations all of the other broadcast in 1080i.

720p programs can handle motion better since they are trenasmitting 60 frames per second.

1080i broadcasts 30 frames per second and the quality of programs with a lot of motion will vary with the quality of the motion compensation being applied with the displays de-interlacing chip/logic.

I have never heard of a 120Hz HDMI cable since the HDMI standards require all video be at 60Hz or less.

Many TV manufacturers are having QUALITY problem with their first 120Hz implementation so you need to try with it enabled and with it disabled to see whiich you like best.
 

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Quote:
Originally Posted by walford /forum/post/15465431


720P programs will look better on a 720p unit then on a 1080p unit since no invention of the additional 1 million pixels has to be performed.

Always? Nope.
 

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I just bought a 40 inch. Sony 120hz 1080p and a HR22. I had a old HDMI that i am using for the DVR to the TV. I am not sure if it's my TV,HDMI or the DVR, but when watching the Tv it look ummm 3dishh in a bad way only when fast movements I guess you can say. Have you had anything likE that?
 

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Quote:
Originally Posted by walford /forum/post/15465431


only ABC , FOX and ESPN-HD broadcast HD programs in 720p.

Other Fox and Disney owned or operated networks also broadcast 720p, such as:

ABC Family

Disney Channel

all the regional Fox Sports Nets

Big Ten Network
 

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What I've noticed is that 720p programming tends to exhibit fewer compression artifacts than 1080i programming. Macroblocking occurs sporadically in 1080i content, especially during sports broadcasts when everything on screen is moving, or when they flash a high resolution graphic that flies all over the screen. With bitrates running around 17-19 Mbps (for MPEG2 video), it seems that the 12% fewer raw pixels per second in a 720p stream allow for a better video encode.


My TV is a true 720p, so that might influence my observations a bit. I don't see a difference between the 1080i channels and the 720p ones, other than the compression issues I mentioned above, and slightly more motion blur during fast scenes in 1080i content.


One thing that is true, however, is that resolution isn't everything. It is certainly possible for a lower resolution video file scaled up to look better than a higher one if they're running at the same bitrate. MPEG-2 has something to do with that, since it's not optimized for low-bitrate applications like the newer codecs AVC/H.264 and even VC-1/WMV-9. Basically, what can happen is that when the content is encoded for broadcast--and is reduced in bitrate from whatever it was recorded/filmed at--compression can degrade the image more if run at a higher resolution, since the codec is trying to take jam more information (in terms of pixels) into the same amount of space.


Think of it like trying to pack a suitcase for a permanent move. If you try to jam your entire wardrobe in there, you'd really have to mash up everything and jam it in there, and when you take the clothes out, they'd be all wrinkley and not really wearable. If you only tried to jam, say, your summer clothes, in there, you might still have to wrinkle everything up, but what you'd get would be a lot more tolerable than in the first case. The optimal situation would be to get a suitcase big enough for EVERYTHING you own, but that might not be possible, because they don't make suitcases infinitely large. (In this analogy, the clothes are your content, and the suitcase is the bandwidth limitation that broadcast imposes.)
 

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Quote:
Originally Posted by Sony40w /forum/post/15470229


I just bought a 40 inch. Sony 120hz 1080p and a HR22. I had a old HDMI that i am using for the DVR to the TV. I am not sure if it's my TV,HDMI or the DVR, but when watching the Tv it look ummm 3dishh in a bad way only when fast movements I guess you can say. Have you had anything likE that?

Go into your video settings and you can turn off this enhancement. What model sony?
 

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Quote:
Originally Posted by Sony40w /forum/post/15470229


...when watching the Tv it look ummm 3dishh in a bad way only when fast movements I guess you can say.

Translation?
 

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Quote:
Originally Posted by Trek7300 /forum/post/15465365


When you first go to this site ( www.avsforum.com ) before you click on the "Forums" tab, they are right now running an article about this very subject. Bottom line: 720p is better for fast action sports. 1080i CAN be slightly better for dramas and film based 24 fps material.

De Facto statements about this subject are invariably wrong. Which is better is a question that has been debated here for years, without resolution.


For example, it's a commonly repeated axiom that 720p is better for fast moving live video, like sports. This has been consistently contradicted over the years by AVS user reports, which prefer 1080i by large margins.

Quote:
But, then again it can depend alot on your source provider (cable, satelite, etc) and how much they compress the signals.

There are many things that can happen to the HD signal between it's source and end user's displays, most of them not good.
 

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I totallyh agree with KenH in post #12 above.

In the earlhy 1990s when the ATSC standards were estabished the statment about action content was true which is why some networks chose 720p.

Today it is not longer true because of the increase in processor power available and that has enabled the use of individual pixel adaptive de-interlace motion compensation code for interlaced programs.
 

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Quote:
Originally Posted by Sony40w /forum/post/15470229


ummm 3dishh in a bad way

That sounds like Motion Enhancer is on High. I am assuming your TV is a Sony based on your name. Motion Enhancer is on Sony sets.
 
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