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Quote:
Originally Posted by Artwood /forum/post/0


At the DVD Forum most of those people are 480i and 480p worshipers.


Are 720p and 1080p worshipers more advanced?

I have wittnessed this as well. It goes like this "Why should I buy something with higher resolution when 480p on my old CRT looks great?"


My advice to them is quit watching the crappy store feeds at BB or CC and find someone who has an upconverting player and watch their favorite action scene on a 720 or 1080 i or p. This will change the way you look at things.


Durring my search I took my own palmtop DVD player with me along with a couple of DVDs to play on sets so I could see how they handled 480. The reality of what some sets could do with the content of a simple DVD didn't dawn on me until a sales guy at a local B&M store took my DVD of Revenge or the Sith and put it into a 1080p player and displayed it on a 52" LCD. As the opening scenes of the battle in space unfolded, my jaw droped and my wallet opened.


I don't think that we are more advanced, just more informed/experienced.
 

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Quote:
Originally Posted by Elemental1 /forum/post/0


Bingo!

The LCD crowd will deny this forever along with the off axis viewing but it is true.

This is a sheen effect and, to me, it is worse than any reflections other than direct sunlight on a plasma.

It just makes you wonder what kind of PQ these LCD guys think is acceptable for HT.


Hopefully most consumers won't use the 1080p spec on an LCD to sway them away from clearly superior plasmas, 1080p or not.




I fall/fell into this...I'm still considering a 42 LCD 1080p or a 42inch Plasma. The thing that really bugs me about the plasma's I've seen that are 42 to 46 inches is they're 1024x768 and it makes me wonder about serious distortion when viewing widescreen and/or HD content.
 

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With 42" set, plasma or lcd, the general concensus is that you would need to sit within 6' of the set to see the full value of 1080p. I believe with modern video processors, a 1024x768 picture would look fine. Of course there is a trade off since it does not display the full 1280x720 hd resolution. With modern LCDs you can sit nearly 80 degrees off center enjoy a great picture with no sheen.


Your best bet is to view various sets of both technologies and the buy the set that you like best.
 

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May I ask which modern LCDs?


I had the Sammy 4095 & Sony KDL 40v2500 set-up in my house and no way would I say 80 degrees and still a great picture. Are we just having a difference of opinions or did I check out the wrong models?


Thanks!
 

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Maybe I've just seen the wrong sets/LCD's but the wife and I looked at them this weekend and LCD looked really good in bright scenes but all the dark scenes and/or shadows seemed flat and lacked detail. Which is a big negative since I'm used to my sony CRT that really produces great blacks.
 

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Quote:
Originally Posted by ebernazz /forum/post/0


May I ask which modern LCDs?


I had the Sammy 4095 & Sony KDL 40v2500 set-up in my house and no way would I say 80 degrees and still a great picture. Are we just having a difference of opinions or did I check out the wrong models?


Thanks!

JVC LT-XXFH96/97. I can walk all around the set and it does not wash out until I get to nearly 90 degrees off center. Also, my home has a bridgeway over the family room, I can look down on the set from nearly directly above and the picture looks great.
 

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Quote:
Originally Posted by 6SpeedTA95 /forum/post/0


Maybe I've just seen the wrong sets/LCD's but the wife and I looked at them this weekend and LCD looked really good in bright scenes but all the dark scenes and/or shadows seemed flat and lacked detail. Which is a big negative since I'm used to my sony CRT that really produces great blacks.

I admit that black is not an lcd strong point. When compared to CRTs plasma misses the mark as well. The current LCDs are closing the gap.


I don't know which sets you viewed but I am going to wager none of them were properly adjusted/calibrated. The detail you desire is provided through good contrast and gray scale tracking.


Home Theater calibrated and tested a Pioneer Pro-FH1 and a Sony KDL-46XBR2. In no way do I believe these results are representative of the entire market but in this case the LCD achieved a better a black level and higher CRs - testing was reported from full-on/full-off and ANSI tests.


For the FH1 the results were:

Full-on/full-off measured CR was 555:1

ANSI measured CR was 930:1

Best measured black level 0.032 ft-L


And for the Sony the results were:

Full-on/full-off measured CR was 1,401:1

ANSI measured CR was 1,217:1

Best measured black level 0.018 ft-L
 

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Quote:
Originally Posted by Nmlobo /forum/post/0


I admit that black is not an lcd strong point. When compared to CRTs plasma misses the mark as well. The current LCDs are closing the gap.


I don't know which sets you viewed but I am going to wager none of them were properly adjusted/calibrated. The detail you desire is provided through good contrast and gray scale tracking.


Home Theater calibrated and tested a Pioneer Pro-FH1 and a Sony KDL-46XBR2. In no way do I believe these results are representative of the entire market but in this case the LCD achieved a better a black level and higher CRs - testing was reported from full-on/full-off and ANSI tests.


For the FH1 the results were:

Full-on/full-off measured CR was 555:1

ANSI measured CR was 930:1

Best measured black level 0.032 ft-L


And for the Sony the results were:

Full-on/full-off measured CR was 1,401:1

ANSI measured CR was 1,217:1

Best measured black level 0.018 ft-L

Interesting. The TV's at the store probably weren't properly calibrated so that is a good point. I've become spoiled on the dark end by my Sony tube
 

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Quote:
Originally Posted by 6SpeedTA95 /forum/post/0


Maybe I've just seen the wrong sets/LCD's but the wife and I looked at them this weekend and LCD looked really good in bright scenes but all the dark scenes and/or shadows seemed flat and lacked detail. Which is a big negative since I'm used to my sony CRT that really produces great blacks.

In bright lighting an LCD can't be beat. You've obviously seen bad ones. My 37" 1080p Akai beats out my Mits CRT-RPTV for black levels in a bright (daylight) room. Shadow detail is damn close. Picture is not flat- this has to do with contrast levels. The Mits screen reflects more light than the LCD and it can't go near as bright. LCDs have come a long ways in the 2 years since I bought the Mits. Don't know how you can stand reflections and glare off that CRT.
 

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Sorry if this question is redundant. I have a panny th-42px60u. I'm watching from 10' away. I have time warner cable and SA 2350hd box watching using componet cable connections. I have 2 questions. What would be the best setting for the cable box 720p or 1080i for the HD channels? I have the box set for pass through in the settings menu. Also I'm watch the basketball tourney and when there is a lot of motion the picture has some artifacts, with little movement the picture is great. Right now the settings on the cable box are 1080i and 480i.

Thanks for the help,


Mike
 

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Quote:
What would be the best setting for the cable box 720p or 1080i for the HD channels?

The best setting is all native.


If your TWC box uses the Passport software, check 4:3 480i, 720p, and 1080i resolutions in Settings -> Settings and choose native output.

Quote:
Also I'm watch the basketball tourney and when there is a lot of motion the picture has some artifacts, with little movement the picture is great.

That is due to excess compression, most likely applied by Time Warner. If you think it's bad now, you haven't seen satellite --Dish and DirecTV are significantly worse.


If Verizon FiOS is available in your area, you can eliminate most of this artifacting by switching to that provider. They supply more bandwidth to their high-definition feeds, which eliminates many of those artifacts you see now with motion. Of course, FiOS can't do anything about local channels that devote too much of their bandwidth to multicasting or datacasting. But at least the HDTV cable channels are pristine, and you get the best possible quality from your local affiliates (which may or may not be pristine, depending on how much bandwidth these local channels devote to HD).
 

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Thanks for your help. I don't see the settings you recommended on the settings, settings menu. Under settings, settings menu I under picture format I have a choice of pass through, fixed, upconvert 1 and upconvert 2. To select the settings I have used, I have to turn off the stb and enter setup mode where it gives me the choices. I don't have a choice of "native settings" that I can see. Would it be called a by a different name. I'm not sure what software is on the stb. Thanks again for your input.


Mike
 

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Quote:
Originally Posted by bfdtv /forum/post/0


The best setting is all native.

The most popular HDTV signal is 1920x1080i. Why are all LCD manufacturers rushing out 1080p LCD sets. Wouldn't a 1080i set be "better" for TV?
 

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No new TVs can display interlaced signals natively. They 'blit' (block transfer) the entire image in ONE SHOT to the display. Inherently progressive. Only.


Hence 1080p - an easy (usually, except when there is motion between half-frames) deinterlace step and 'flawless' display.


On 720p TVs, there is a deinterlace step, then (sometimes) a downscale step (540p) then an upscale to 720p, or (sometimes) a direct 1080p->720p scale step.
 

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Quote:
The most popular HDTV signal is 1920x1080i. Why are all LCD manufacturers rushing out 1080p LCD sets. Wouldn't a 1080i set be "better" for TV?

Keep in mind, 1080i is only the delivery format, aka the box in which the contents arrive. With more than 75+% of all programming on broadcast and cable, the actually contents of that package are 1080p24, just like you get with Blu-ray and HD-DVD. See below:

Quote:
On broadcast and cable, we have two sources of high-definition material on 1080i channels. We have video-sourced content, such as sports, acquired natively in 1080i60. We also have content acquired in 1080p24 with a HD camera or telecined from film, but flagged as 1080i60 for broadcast.

Video-sourced content


In the case of video-sourced material such as sports, we have 60 different 1920x540 fields, all acquired at different points in time (separated by 1/60th of a second). Because the fields were all acquired at different points in time, they don't "match up" when there is any movement on the screen. Attempting to combine every two fields to form a 1080p30 image would result in severe combing. Some older (and many cheaper) TVs simply "bob" to display 540p resolution, by taking each field and making it a frame without adding any new picture information. That was the old/cheap way of doing things.


The better displays on the market interpolate new information to create a full 1080p60 signal through a process known as motion-adaptive deinterlace. Adjacent fields are compared to determine what pixels are in motion. Areas of the picture that aren't in motion -- such as background scenery that did not move in the previous 1/60th of a second -- can be weaved together at full 1080p resolution. Areas of the picture that are in motion -- and did move in the previous 1/60th of a second-- are created by bobbing, or in some cases, averaging the information in adjacent fields, and will vary in resolution between 540p and ~1080p. Whether pixels in motion appear as 540p or closer to 1080p depends on the rate of movement, as well as the quality of the video processor in the display. Not all motion-adaptive deinterlacing is equal -- far from it.


Most newer 1080p displays do region-based, motion-adaptive deinterlace for 1080i60 video sources. With this approach, the video processor divides the screen into lots of different regions or boxes, and then compares 1-2 adjacent fields (2-3 total) to see if anything has changed in those boxes in the last 1/60 of a second. If nothing has changed in a box (ex: part of a billboard), the processor "weaves" in the information from the previous field, providing full 1080p information for that box. If something has changed in last 1/60 of a second, the processors "bobs" to display 540p resolution for that box.

Even among products with region-based, motion-adaptive deinterlace, there are probably significant differences, depending on the computional power of the processor. For example, one display might divide the screen into 64 regions and another might divide it into 256.


Contrast that to pixel-based, motion-adaptive deinterlace solutions like Gennum VXP and Silicon Optix HQV. Rather than divide the screen up into large regions, those solutions compare every pixel across three or four adjacent fields (4-5 total) to determine what pixels are in motion and which are not. Weave and bob decisions are made individually for every pixel on the screen, rather than for larger regions of the screen at once. Since they compare more fields, these processors can also better determine the properties of the motion to apply motion compensation or a multi-directional diagonal filter, if appropriate. It should be fairly obvious why this more comprehensive -- and computionally intensive -- approach can yield superior results.

Film-sourced and 1080p24 content


In the case of 1080p24 content -- such as movies and television series -- all this is interpolation is unnecessary. Few people realize that virtually all movies and series content shown on CBS, NBC, HBO, Starz, and Showtime is actually full 1080p, just like Blu-ray and HD-DVD. There is no need to interpolate anything, because the full information for all twenty-four 1080p frames is already there. With 1080p24 content delivered in a 1080i60 signal, you have the following:


Frame1, Field1

Frame1, Field2
Frame1, Field1

Frame2, Field1

Frame2, Field2

Frame3, Field1

Frame3, Field2
Frame3, Field1

Frame4, Field1

Frame4, Field2

Frame5, Field1

Frame5, Field2
Frame5, Field1


This is known as a 3/2 cadence. You have three fields of one frame, two fields of the next, and the cycle repeats.


The fields highlighted in bold are sent using repeat flags, a few bytes which tell the MPEG-2 decoder to repeat a previous field. Only 48 unique fields of information -- each containing half the information in a full 1080p frame -- is typically transmitted every second with 24p content. Compare that to 1080i video, such as sports, where 60 different fields of information is sent every second. For that reason, 1080p24 source content requires less bandwidth to broadcast than video, not more.


The only hardware that has access to those repeat flags is the MPEG decoder inside the STB/DVR or HD-DVD player. Once the MPEG (or VC-1) bitstream from broadcast, cable, or HD-DVD is decoded by the STB, DVR, or HD-DVD player, there are no more flags. All you have at that point is the cadence.


The display processor can't simply combine every two fields, because they don't match up. Instead, the display must reconstruct the original 24 1080p frames through a process known as inverse telecine. Inverse telecine produces an image that is identical to the original 1080p source. To do this, the display processor must determine the cadence of the input signal by comparing the fields. If every field is unique, then the source is video. If every fifth field is a duplicate, then the display processor knows that the source is 24p**; it can eliminate the duplicate fields and reconstruct the original 24p frames. Once this is done, pull-down is applied to repeat the full 1920x1080p frames to match the refresh rate of the display (i.e. 60Hz). At that point, depending on your TV, the image is output directly to the screen, [or] digitally scaled to add overscan, or digitally scaled to fit a lower-resolution panel. On a display that correctly performs inverse telecine, there will be no difference between the 1080i and 1080p output from a Blu-ray player.


Most modern displays can detect the 3/2 cadence on 480p24 content flagged as 480i60 (i.e. DVD), but only a minority can do the same with 1080i60 signals. It is more computationally intensive to do this with high-definition, and many display makers skimp on high-def processing to cut costs. On displays that cannot detect the 3/2 cadence necessary to reconstruct the original 1080p frames, they treat the source as video. They either bob to display the signal as 540p -- as was the case on older/cheaper displays -- or they do motion-adaptive video deinterlace to interpolate the remaining information for the 1080p frame.


Progressive frames created from interlaced content through interpolation will never be as good as material originally acquired in 1080p and reconstructed with inverse telecine. The greatest differences are seen when there is a lot of movement on the screen, because all the information for that motion exists in a progressive source, but does not exist in an interlaced source.


If you've ever seen combing, blurring, moire, stairstepping, or other interlace artifacts on movies or series content shown on CBS, NBC, TNT, HBO, or SHowtime, chances are it was because your display could not correctly perform inverse-telecine. Unfortunately, most displays do not have quality deinterlace -- of the displays tested by Home Theater Magazine (more results here ), only seven of the 61 tested would offer the same performance with a 1080i input as they do with a 1080p input. In its latest issue, Home Theater Magazine reviewed and compared the top 60" 1080p RPTVs from JVC, Mitsubishi, Olevia, Samsung, Sony, and Toshiba. Only two of the six could correctly detect and display 1080p24 content delivered in a 1080i60 transmission, such as Heroes on NBC and CSI on CBS.


Things become a bit more complicated when you have content with "bad edits," as you often get when film and video sources are mixed together. Further, while the actual movie or series may be a 1080p24 source, it's common for commercials to be video sourced. Hence, the display's processing has to be able to switch between video and film modes on the fly, based on what it detects as the source content (60i or 24p). Not all video processors and displays are able to do this well. Some display processors can detect and switch between video and film mode relatively fast (within a few seconds), whereas others may take 30-60 seconds.

** It's not actually quite this simple. Most film-sourced content on cable and broadcast is distributed with the appropriate repeat flags to minimize bandwidth use. But there are times when film-sourced content is distributed and compressed like video. Generally, broadcasters and cable companies like to avoid that, because it wastes bandwidth, but not every broadcast affiliate uses modern encoding equipment.


When content is distributed without those flags and compressed like video, the cadence is still 3/2, but due to compression, every fifth field may not be bit-for-bit identical to a previous field. Hence, to provide reliable inverse telecine, a display processor must not only detect identical repeated fields, but it must also detect when every fifth field is nearly identical. This analysis requires more computational power. Some implementations like the Silicon Optix ReonVX and Realta have the processing power necessary to do this, while other solutions, like those found in Pioneer plasmas, apparently do not.

Home Theater Hi Fidelity also posted a more comprehensive article with illustrations below:

High Definition 1080p TV: Why You Should Be Concerned
 

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Is there any real 'proof' that broadcast signals contain these flags?

Are they not already converted at the source?
 

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Quote:
Originally Posted by windsor2 /forum/post/0


Thanks for your help. I don't see the settings you recommended on the settings, settings menu. Under settings, settings menu I under picture format I have a choice of pass through, fixed, upconvert 1 and upconvert 2. To select the settings I have used, I have to turn off the stb and enter setup mode where it gives me the choices. I don't have a choice of "native settings" that I can see. Would it be called a by a different name. I'm not sure what software is on the stb. Thanks again for your input.

I assumed you had Passport. It sounds like you have SARA.


With SARA, enable 4:3 480i, 720p, and 1080i in Advanced setup (turn the box off, hold down guide and info buttons), and enable passthrough / AutoHDMI in Settings - Settings. Passthrough and AutoHDMI are the same thing; AutoHDMI is what you see when a HDMI cable is used, passthrough is what you see when component cables are used.
 

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Quote:
Originally Posted by Elemental1 /forum/post/0


Is there any real 'proof' that broadcast signals contain these flags? Are they not already converted at the source?

All modern broadcast equipment encodes the appropriate flags.


However, even if some broadcaster or cable company has misconfigured their equipment, or is using a ten-year old encoder without the ability to properly apply flags for efficient transmission, it doesn't change the signal that is sent to your TV. Recall the example given in my previous post for the field sequence used by a 1080p24 source packaged in 1080i60:


Frame1, Field1

Frame1, Field2

Frame2, Field1

Frame2, Field2
Frame2, Field1

Frame3, Field1

Frame3, Field2

Frame4, Field1

Frame4, Field2
Frame4, Field1


The primary difference between a flagged and unflagged transmission is the latter actually sends those fields as part of the broadcast/cable signal, rather than using a bit that says to repeat the previous copy of that field. Flags just eliminate extra copies of the same field for transmission, saving bandwidth. Flagged or unflagged, the signal sent to your display by the box (or the TV's built-in decoder) doesn't change. Flagged or unflagged, your display still receives a signal with the same cadence.
 

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after reading this thread, i have a huge headache. Some of you say with a 40 inch lcd 1080p wont do anything for you, then some more people chime in and say BS, it does matter. WTF, I can probably afford a 1080p but if its not going to matter with a 40 inch lcd watching at 8 feet, why should i spend the extra $500, when I can go and buy a PS3 instead.... CNET claims it wont matter at 8 feet and 40 inches, and it only matters after 50 inches. This whole debate is not being won by either side for me.... this sucks
 
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