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Discussion Starter #1
In the review of a Panasonic HDTV in issue 39 of The Perfect Vision, Gary Merson states that WNET, a PBS station, is broadcasting true 1080i HDTV. Are there some station out there that aren't broadcasting true 1080i or 720p HDTV? If so, does somebody out there have a list of stations that aren't? Also if these stations are not sending out a true HDTV signal, then what are they sending? What about the stations here in Atlanta GA, are they broadcasting the real thing?
 

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This is an interesting debate that's gone on here alot. You might want to do a search for "720p" as there are debates everywhere over whether 1080i or 720p provides better picture quality.


By the numbers, 720p is 1280 x 720 resolution, with 60 progressive frames per second. 1080i is 1920 x 1080 resolution, with 60 interlaced fields per second.


Because of the idiocy that went on at the time of HDTV spec's ratification, I don't think anything can be called 'true HDTV.' The HDTV cameras and equipment are expensive enough without each manufacturer having to provide total duality between 1080i 30fps, 1080p 24p (which can't be received or displayed by any HDTV), and 720p.
 

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Quote:
Originally posted by feldon23
By the numbers, 720p is 1280 x 720 resolution, with 30 progressive frames per second. 1080i is 1920 x 1080 resolution, with 60 interlaced fields per second.
Isn't 720p 60 frames per second (vs 1080i's 60 fields per second)? That's what the FAQ says (under the heading "Why are there so many DTV standards? Isn't that overly confusing? Can you explain them?").


-- Mike Scott
 

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720p is 60 frames per second. That was probably just a typo by feldon.


However, I don't think that the original poster was asking about 1080i vs 720p (they're both "true" HD formats). Rather, I believe that he was referring to stations doing digital but not HD (a la Fox). Can you clarify your question, Ron?
 

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Yes 720p is at 60 frames per second. I think titantv.com lists digital TV stations and their status. Note that the FCC DTV mandate does not require any HDTV. You can simply go on with 480i, even NTSC that is re-packaged in the DTV format. Along those same lines, 1080i or 720p may in fcat be HDTV scan rates but this does not mean a high quality picture. An example is HBO or SHowtime HD. They are always in 1080i mode but if they are showing a non-HDTV porgram, it's still only 480 lines worth of resolution that is artificially made into 1080. This process is called "upconversion".


But there is a growing list of good HDTV program material these days. CBS prime time is all true HDTV. ABC has just joined in this season with a substantial primetime HDTV linup. Both DirecTV and Dish operate an HDTV PPV channel. HBO and SHowtime have HDTV channels, HBO has far more content. And recently DirecTV added HDnet. This is a variety channel with a heavy emphasis on sports.
 

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Saying "true" HDTV may be a bit too vague for us to know what they meant.


Alot of shows are filmed and then later telecined

to digital HDTV tape. Even though they are

broadcast in 1080i (on HBO or CBS for instance),

the stuff done from film conversion doesn't

look as sharp and crisp as "true" direct to

digital HD/CAM type video. Also film converts

tend to be 24fps whereas video is 30fps so you

get a bit better motion with "direct to video".


Anyways, PBS does show some programs

(like "Smart Travels") which are shot directly

to HD-video so it could be that is what they

are talking about when they say "true HDTV".
 

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This brings up a good point though...


I have often wondered why some HD shows look better than others. For example, The Tonight Show looks great 9 out of 10 nights. On the other hand, That's Life on CBS doesn't look nearly as good. Both are 1080i (TRUE HDTV), but one looks clearly better. I guess it's a better "transfer"?


I wonder if there isn't better equipment and better use of it going on.


OUT
 

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Discussion Starter #8
Quote:
Originally posted by vruiz
However, I don't think that the original poster was asking about 1080i vs 720p (they're both "true" HD formats). Rather, I believe that he was referring to stations doing digital but not HD (a la Fox). Can you clarify your question, Ron?


You are quite right VRuiz. I am not concerned about 720p vs 1080i. I was questioning if when watching a so called 1080i or 720p program am I getting the real deal. In other words, how do you know when you're watching a 100% pure HDTV program as opposed to one that's been upconverted?


If I'm going to spend thousands of dollars on a new HDTV set then I would like to think I'm watching the real thing and not some 480i program that's been upconverted to 1080i or 720p! Does anyone here in Atlanta know if the HDTV stations are sending out a pure HDTV signal or are they upconverting to? What about the satellite systems?
 

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Quote:
Originally posted by McPatrickClan
I have often wondered why some HD shows look better than others. For example, The Tonight Show looks great 9 out of 10 nights. On the other hand, That's Life on CBS doesn't look nearly as good. Both are 1080i (TRUE HDTV), but one looks clearly better. I guess it's a better "transfer"?
The answer is that "The Tonight Show" is not a transfer at all. There are two types of HDTV, film-based and video-based. Live shows (like sports) or live-to-tape shows (like The Tonight Show) are done using HD video cameras and/or HD video tape, which gives you that "like being there" look. HD video gives a sharper picture but is less manageable in things like contrast ratio and depth of field which are important for dramatic storytelling.


Most episodic TV (sitcoms and drama series) is shot on film (like movies), which is a more appropriate visual medium for that purpose due to its superior ability to capture the mood and lighting essential to the director's vision of the story he wants to tell. The film is then transferred to HD tape for broadcast and archival purposes. Transfer quality varies according to the source and the director's artistic intent. Good film transfers can be every bit as detailed as video HD, they just have a different look. "That's Life" however, is not one of them. If you want to see good detailed film HDTV check out "Family Law", "Judging Amy", "CSI", or "The District".


I am of the opinion that neither one is "better" than the other. Each one has its purpose. Sports, news, talk shows, and documentaries lend themselves very well for video production. Sitcoms, dramas, and movies do not, and are better done on film. HD video is not better than film transfer, it just has a different look. They are both true HDTV.
 

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>>>>> Good film transfers can be every bit as detailed as video HD


I don't completely agree.


I have never seen a film transfer with the

detail of a good HD-video show like

Smart Travels on PBS.

They can come close, but the film grain starts

to become a limiting factor.
 

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Ok, maybe I should've said "very close" instead of "every bit", but I submit that very close is still pretty good ;) . If you had seen some of the older movie transfers like "The Last Emperor", "Les Miserables", or "Geronimo: An American Legend" you would probably agree. You don't see transfers like those anymore, thanks to HBO and probably the MPAA.


I recommend catching "The District" on Saturday nights, for the very best film-based HD can currently offer.
 

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Believe you should factor in how often equipment is used, primarily Sony HDCAM, that limits full-screen 16:9 horizontal to
 

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Quote:
Originally posted by John Mason
Believe you should factor in how often equipment is used, primarily Sony Betacam, that limits full-screen 16:9 horizontal to
 

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I think that due to limitations in human visual acuity you'd have to have 20/20 vision or better (mine is 20/15 on a good day with my contacts freshly cleaned) and be viewing within 10 feet of a 70-inch screen to be able to see the difference between 1440 and 1920, assuming the display could actually display 1920 horizontal pixels in the first place. In other words, this is an issue (if you can call it that) for high-end, front projection systems only. I doubt even my 64" Zenith RPTV with its 9-inch CRTs can actually display 1920 horizontal pixels. It would be fun to view an HDTV test pattern to see what it CAN do though!:) So, unless you're buying a 35 thousand dollar FPTV and a 100" screen (and I realize some of you guys have done just that!) I wouldn't lose too much sleep over this.
 

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John, are you aware of an online source for HDTV test paterns?
 

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Getting back Ron's original question. In Atlanta CBS and NBC are capable of 1080i and ABC does 720p. These are all 'real' HDTV, but only when an HDTV source is available from the network. If an HD source is not available for a given program, the signal will be either 480p or 480i. Fox is always 480p or 480i, but they do several widescreen programs.


WPBA (PBS) has already stated that they will initially not be able to do true HDTV when they go digital early next year. The local WB, UPN, and WTBS are also going digital in 2-3 months, but likely will not have any HD content for a while.


More information is available at:
http://www.atlantadtv.org/
 

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Wish more HDTV stations had test (resolution) patterns, David. Someone mentioned in a thread last year that his local station did. There are some commercial software programs for HDTV resolutions. If you feed a computer-card HDTV component signal into your set, bypassing your HDTV receiver, that'll tell you something about your set, but IMO it still wouldn't be telling you what an OTA HDTV signal delivers after filtering.


As I've suggested before, think all the networks could incorporate some simple patterns into their standard brought-to-you-in-HDTV screens. They appear only briefly, but you could eventually pin down your set's on-screen performance. Next step, who knows when, is an Avia HDTV test disc. -- John
 

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Quote:
Originally posted by PVR
>>>>> Good film transfers can be every bit as detailed as video HD


I don't completely agree.


I have never seen a film transfer with the

detail of a good HD-video show like

Smart Travels on PBS.

They can come close, but the film grain starts

to become a limiting factor.
And I have never seen a video produced show with the depth of field you get with film.


It just a different look. It is highly subejective which is best. I like to believe they both have their place.
 
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