Why 1080p has no merit, apart from maybe reducing SDE. - Page 5 - AVS Forum
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post #121 of 144 Old 12-26-2006, 04:39 PM
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Originally Posted by jsaliga View Post

Why do you ask?

Because Art said that my finding wasn't his experience. And you posted:
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Originally Posted by jsaliga View Post

Mine neither Art.

So let's hear about the results of your testing. Or did you do any?

[quote=jsaliga]
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You are the one making the claim and the burden rests with you to prove it.

I'm not making any more of a claim than you are. At least I've purchased 2 projectors, put them in a room side by side, and tested them. Have you?

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The fact you are a physician has no bearing whatsoever on the topic.

It has bearing that I don't need your explanation of a double blind test or definitions of common words. When you do those things, it doesn't make you look smart. It makes you look condescending. Especially if you haven't done any of this research yourself.

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You claimed to have conducted a double blind test and I challenged your assertion. I think it is pretty clear that you have not done a valid double-blind test, and I'm not sure why you felt it necessary to say you have when you did not.

In each case, the person viewing did not know which projector they were seeing and the person doing the switching did not know which projector was showing. That's double blind. Yes, there are more rigorous forms of testing, but that is in fact double blind.


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Originally Posted by jsaliga View Post

And rest assured I am not arguing against you.

I will rest just fine, but you most certainly are arguing against me. See your first quote above.

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But I am suggesting that you have not met your burden of proof.

I've met my burden of proof infinitely more than you have yours. If you wish to challenge my statement that there is no more detail based on actual testing, then it is you who has the burden of proof to show us otherwise.

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I think you and Jones_Rush have posted some thought-provoking ideas, but I am unable to draw any meaningful conclusions from this thread. The only thing I can conclude at this time is that a valid double-blind test with the proper controls might be more informative. It might also be impossible marshall the resrouces to do.

I'm so sorry you're disappointed. But no one asked you to read this thread, and you've contributed exactly nothing meaningful to the topic because you haven't seen anything with your own eyes.

But you do seem quite adept at using a dictionary.
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post #122 of 144 Old 12-26-2006, 04:44 PM
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Originally Posted by jacksonian View Post

Show me the "established experience" to refute my statement other than videophiles assuming that the 1080p pj will have more detail.

It is a logical and reasonable conclusion based on available facts and collective experience.

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Until one of you guys who likes to criticize puts your money where your mouth is and does the test better than I did, you don't have any room to talk.

I'm not really sure where all of this hostility is coming from. I may have questioned your methods and have doubts about your results and conclusions, to be sure. But I don't recall having made any personal attacks against you or said anything to call into question your character. My comments so far have been from a dispassionate perspective. If you think otherwise then I appologize; it certainly wasn't my intention.

--Jerome
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post #123 of 144 Old 12-26-2006, 04:55 PM
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Originally Posted by jsaliga View Post

It is a logical and reasonable conclusion based on available facts and collective experience.

Really? Please show us these facts and collective experiences of actual testing. I'm unaware of their existence. I am, however, aware of people frequently making "logical and reasonable conclusions" that are absolutely incorrect and based on zero actual testing. That's why we do the testing.

I'm going to ask you again, what testing have you done? You agreed with Art when he said that wasn't his experience. So that means you have some experience to speak of, correct?


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I'm not really sure where all of this hostility is coming from.

There's no hostility here. You have challenged what I've said with absolutely zero personal experience, and until you can produce it, absolutely none of this "collective experience" that you have used as your data point. You have also quoted the definition of a simple word for me, and that can only be taken as condescending.

My comment on putting your money where your mouth is was self explanatory. Being a keyboard jockey doesn't qualify your opinion as valid. If you have done some testing, I would certainly welcome your thoughts on the subject.
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post #124 of 144 Old 12-26-2006, 05:09 PM
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Originally Posted by jacksonian View Post

You have challenged what I've said with absolutely zero personal experience

You mean no personal experience of which you are aware.

I could go into all of that but I won't because it really has nothing to do with your tests and results and to do so would not be a productive use of my time. Since you seem more interested in making this a debate about me than you are in discussing your methods and results I don't see any real benefit in continuing this discussion.

And despite what you say I'm sure you would rather have me gone from this thead, so gone I'll be. Enjoy your thread.

--Jerome
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post #125 of 144 Old 12-26-2006, 05:34 PM
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I think this is thread is turning into a flame for no good reason as both sides are bringing up some good points. Jerome, I think Jacksonian at least attempted to do as fair a comparison as possible. I don't give it any authoritative value and I question the conclusions, but I think he did his best to do a fair comparison which is more than can be said for the majority of the absurd "comparisons" on the forum such as "I saw the Pearl at Dealer A and the Ruby at Dealer B and the Ruby blew the Pearl away".

That's an observation which has nothing to do with my following comment..
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Side by side, same time, same screen? I just did it with the Epson TW700 and TW1000 and posted tons of screenshots. I could NOT see any difference at all in detail between the two.

I have not read the entire thread but this prompts several questions.

1. What was the source material? All HD is NOT the same.

2. You compared two LCD projectors from Epson. I am not familiar with Epson projectors nor their MTF or what the most recent fill factor measurements are on LCD. Nor what the quality of their lenses is. In other words, regardless if the number of pixels, are their other aspects of performance "up to the challenge" of revealing the differences between the two resolutions. One question is would you have come to the same conclusion comparing two DLP projectors of different resolutions. Or any other number of combinations.

Resolution is one factor affecting detail. MTF is another. Here is an excellent post that was written by Greg Rogers of Widescreen Review. Greg is perhaps the best video reviewer on the planet (he is in my opinion). You may find his post useful.

Quote:


Sorry I can't hang around 24 hours a day and answer these questions as they are posted. Obviously, my comments about sharpness and detail evoked several responses. Instead of going back and responding point by point to all of the posts on the same topic I'll just discuss sharpness and detail here and hope that suffices.

The perception of image sharpness is generally determined by edge transitions. The more abrupt (faster) the edge transitions the sharper the image appears. The lack of sharpness is usually termed softness. Sharpness is a different quality than the ability to perceive detail, which is usually called resolution.

CRT projectors typically appear significantly softer (have less sharpness) than fixed pixel projectors because the brightness of the CRT electron beam spot falls off gradually (a gaussian-like distribution) toward its edges. The pixels on a fixed-pixel projector are basically discrete (have defined edges) hence they can inherently produce sharper image edges, i.e. better sharpness. However, if the discreteness (edge definition) of the pixels is reduced by lens optics, pixel device characteristics, or misalignment of multiple pixel devices the ability of the projector to produce sharpness is reduced. (Just as lens optics, CRT spot characteristics, and misalignment [mis-convergence] reduce CRT projector sharpness). Hence, there are sharpness variations amongst fixed-pixel projectors having the same native pixel density, just as there are sharpness variations amongst CRT projectors.

In the case of the dVision 1080p, the lens optics produced superb focus and virtually no chromatic aberration, which in addition to the discrete DLP mirror structure, and no misalignment of multiple DLP chips (since this is a single chip design), produces unprecedented image sharpness. The difference in perceived image sharpness between the dVision 1080p and the Ruby was not a close call. The difference was dramatic. The edges are sharper than on the Qualia 004 (which has better optics than the Ruby), which in turn is sharper than the Ruby. I devoted a special section (called Optical Performance) in my Ruby review to discussing its optical performance. Here is part of that section:

However, edges are slightly softer on this projector [Ruby] than the Qualia 004. The gaps between individual pixels are more clearly visible on the Qualia, which is likely the result of a higher quality lens with a better MTF (modulation transfer function). The new, smaller panel may also be a factor. Regardless of the reason, high-definition images appear slightly softer and more like a CRT projector, although they are still considerably sharper than a CRT projector.

I might note that panel misalignment has an interesting effect on sharpness (and detail as well). If the panels are greatly misaligned (a pixel or more) it has LESS effect on sharpness and resolution because we then perceive the image as having discrete colored "ghost" lines. It looks terrible, but if you ignore that, it's not really affecting sharpness or resolution because we see multiple image lines. If the misalignment is greater than about 0.5 pixel but less than a pixel, we perceive color fringing, rather like chromatic aberration. It looks poor, and it does affect sharpness and detail, but we are more likely to complain about the color fringing effects. When the misalignment is sub-0.5 pixel we aren't likely to see color fringing from normal viewing distances but sharpness and detail perception suffer. I think the difficulty in aligning 1080p panels/chips on consumer products is going to make it unlikely that 3-chip/panel 1080p consumer projectors will achieve the sharpness/detail that is possible in single-chip 1080p projectors.

I'd like to discuss the artificial sharpness or false sharpness that arises when the pixel density of the projector is lower than required for the edge transitions determined by the video's rise and fall times, or when scaling or electronic detail enhancement or "sharpness" controls, add overshoot and ringing to the signals. But I don't have time to go into that now. However, those are examples of artificial or false sharpness that looks bad, and shouldn't be confused with real improvements in sharpness that arise from a higher native pixel density, superb optics, and electronics that avoid overshoot and ringing artifacts.

Resolution is a measure of the ability to differentiate spatial detail in images. But I normally try not to use the term resolution when describing image quality because it seems to confuse some people. Thanks to the computer industry, some people see the term resolution and immediately equate that to the native pixel format of the display. They seem to think that all 1920 x 1080 pixel displays have the same image resolution. But if resolution specifies the ability to perceive detail, then fixed-pixel or CRT projectors that display the same pixel format (i.e. 1920 x 1080 pixels) will likely have different resolutions. To make this more clear ... the resolution of two CRT projectors will likely be different, even if both projectors produce the same size images, using the same (1080p) scan rates. The resolution of two fixed-pixel projectors will likely be different, even though both have 1920 x 1080 pixel imaging devices.

The ability to perceive detail (resolution) gradually decreases as the size of the detail (increasing horizontal or vertical spatial frequency) is reduced. Therefore, we can best describe the ability to perceive spatial detail with a modulation transfer function (MTF), which measures contrast as spatial frequency is increased (rather like reducing the separation between a series of alternating black and white lines). The shape of the MTF curve (contrast vs frequency) is very different for CRT projectors than fixed-pixel projectors, because it usually depends more on CRT spot size and shape than lens quality. The MTF curve for fixed-pixel projectors is more dependent on lens quality and is ultimately limited by the native pixel format of the projector. The same physical factors that determine sharpness also determine resolution, but the perception of sharpness is mostly a function of the shape of the MTF curve, while resolution is normally defined as the frequency at which the contrast falls to some arbitrary level. For instance, the MTF curve for a CRT projector may start to fall off at a lower frequency but extend to a higher frequency than a fixed-pixel projector. As a consequence, the CRT projector may produce a higher ultimate resolution (finer detail) while producing less sharpness than fixed-pixel projector. In addition, larger detail may be much more visible on the fixed-pixel projector than the CRT projector because the slope of the MTF curves are very different. The same type of effects can occur between different fixed-pixel projectors because their MTF curves also vary depending on their optics and imaging devices.

In the Ruby review (Optical Performance section) I wrote the following about MTF contrast vs maximum spatial frequency (1920 pixels-per-picture-width) to compare the Ruby with CRT projectors:

The AccuPel multiburst test pattern demonstrates that this projector can easily resolve the maximum 1920 pixels-per-picture-width resolution of the 1080i and 1080p video formats. Single-pixel black and white lines are displayed with exceptional contrast using digital signals, and nearly as well using analog signals. The multiburst lines are sharper and the contrast depth is much better than I have seen on a CRT projector.

The dVision 1080p produces even better MTF contrast in the maximum frequency pixel burst (1920 pixels-per-picture-width) than the Ruby, but its steeper MTF curve also improves the contrast for larger detail compared to the Ruby. For instance, the fine lines in the horizontal bar codes on soft drink containers were much clearer on the dVision 1080p than the Ruby during a 1080i D-Theater movie. However, the perceived difference in sharpness is even greater than the perceived difference in detail when comparing the dVision 1080p to the Ruby, although the difference in detail may become even more significant when higher resolution HD/Blu-ray DVDs are considered (they weren't out yet when this evaluation was done).

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post #126 of 144 Old 12-26-2006, 05:54 PM
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Originally Posted by QQQ View Post

1. What was the source material? All HD is NOT the same.

I used the Panasonic Blu Ray player set at 1080i with Training Day, Black Hawk Down, The Great Raid, Eight Below. I used the Toshiba HD-A2 with Batman Begins and King Kong. I used the TiVo S3 with 1080i content recorded from OTA NBC & CBS, Time Warner Cable source of INHD1&2, HDNet, TNT-HD, Discovery HD theater. EDIT: I left out the 720p content from OTA ABC and TWC ESPN-HD

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2. You compared two LCD projectors from Epson. I am not familiar with Epson projectors nor their MTF or what the most recent fill factor measurements are on LCD. Nor what the quality of their lenses is. In other words, regardless if the number of pixels, are their other aspects of performance "up to the challenge" of revealing the differences between the two resolutions. One question is would you have come to the same conclusion comparing two DLP projectors of different resolutions. Or any other number of combinations.

Resolution is one factor affecting detail. MTF is another. Here is an excellent post that was written by Greg Rogers of Widescreen Review. Greg is perhaps the best video reviewer on the planet (he is in my opinion). You may find his post useful.

QQQ, I'm just now learning about MTF. I'll have to read up on that. Let me read it and attempt to digest that.

In my posts as well as the Athens 1080p/720p shootout that was done with DLP projectors (Marantz), it seems that no one can believe the results. And so there's always another factor, whether it be poor source, poor scaling, poor optics, MTF, the need for test wedges, there's always some reason that 1080p *would* have shown an improvement under the right circumstances.

The point I've been trying to make is that in a normal room with normal enthusiast quality equipment and sources, I cannot see any increase in detail between the two. And that is exactly what the 30 or so folks in Greece found.
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post #127 of 144 Old 12-26-2006, 06:23 PM
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I think this is thread is turning into a flame for no good reason as both sides are bringing up some good points. Jerome, I think Jacksonian at least attempted to do as fair a comparison as possible. I don't give it any authoritative value and I question the conclusions, but I think he did his best to do a fair comparison which is more than can be said for the majority of the absurd "comparisons" on the forum such as "I saw the Pearl at Dealer A and the Ruby at Dealer B and the Ruby blew the Pearl away".

QQQ,

No one, least of all me, was suggesting that the comparison was deliberately misleading. I gave the same weight to it that you did; it was very interesting and many of the ideas in this thread were thought-provoking, but in the end I questioned the validity of the conclusions. That was my only real point. That Jacksonian and I butted heads over this is regrettable.

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Resolution is one factor affecting detail. MTF is another. Here is an excellent post that was written by Greg Rogers of Widescreen Review. Greg is perhaps the best video reviewer on the planet (he is in my opinion). You may find his post useful.

I recall reading that post from Greg just a few weeks ago. I wish I would have remembered it. It may have prevented a lot of bad feelings. Thanks for posting it here; hopefully it will avert any further ill will.

What Greg is saying is very consistent with my own experience with a number of CRT and digital projectors that I have owned. I ran a number of tests with the NEC XG110LC and Barco 1209s. The NEC did not have enough video bandwidth to handle 1080p signals. It was an 8" tubed projector anyway so it was not going fully resolve 1080p in any case. But using the same principles it helped to find that projector's sweet spot. On CRTs the picture you get is as much a measure of the person doing the setup as it is of the machine itself and the source inputs. And the NEC XG series are very difficult to do EM focus and astig (spot shape) adjustments. The Barco was a 9" CRT and was far easier to dial into perfection than the NEC. It could take 1080p signals. I had Chuck Willaims (one of the best CRT projector techs around) do the dial in on the NEC XG and I had a local guy who is very good help with the Barco a few years later. At 1080p on the Barco there was most definitely more visible detail since the spot size was much smaller. The same was true of the NEC up to a point. The projector resolved more detail using 1080i deinterlaced and scaled to the projector's sweet spot. Moreso than 1080 signals scaled to 720p. In one case I actually had a clip of the same original HD source material encoded at 720p, 1080i, and 1080p. With the digitals it was a much different experience. On the NEC 1080i or 1080p scaled produced more resolved detail than 720p clip or the 1080p clip scaled to 720p.

There were a littany of items in the video chain of these "tests" for which there were no controls (eg. source devices, video processors, PCs, etc.) I never considered these proper tests, only interesting experiments. In short, at the time I did not even have a signal generator that could do 1080p and 720p test patterns so all I had was sample video to use. It was far from scientific but I was doing these evaluations for my own edification and any flaws in my methodology were not important to me. It wouldn't be for another year or so before someone with an HD signal generator was available to do some additional testing.

I have no idea what the glass is like on these Epson projectors. I was going to research these units after reading this thread but not for several days since I am going out of town tomorrow to visit with family, and won't be back until after the new year. So I won't have any discretionary time until then. But in either case I have already said more than I apparently should have. I wanted to give you the courtesy of a reply to acknowledge your excellent post.

--Jerome
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post #128 of 144 Old 12-26-2006, 06:37 PM
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Enjoy your time away Jerome .
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post #129 of 144 Old 12-26-2006, 08:20 PM
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The current crop of 1080p digitals are still in the state of infancy.
I wouldn't put too much stock in their performance yet.
Right now 720p is the sweet spot of performance/value.

Now if I could afford that pearl wouldn't have said that!

It is all about quality...that is the picture

JVC & NEC 8" CRT with 106" wide Stewart screen. All NHT speakers driven by Pioneer Elite AVR and bluray

Custom dedicated 8 seat theater

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post #130 of 144 Old 12-26-2006, 08:22 PM
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For those currently on the thread debating whether or not they have seen a difference, has anybody tried my test in post #79 on this thread? Short of doing the real thing, I think it's the best way to get as close as possible to the real thing on a computer screen, and it works using both LCD and CRT technology. I think it's a much better way to do the test than what Jones_Rush has tried because it keeps the picture size constant while only varying detail.

Along with the test, I have included the methodology, procedures, and theory I used in order to come up with it so that anybody can debate the methodology used to perform the test.

If you dont' want to go through the full procedure, here is the quick and dirty test picture. Just be sure that your automatic image resizing is off in your internet options. (Tools-->Internet Options-->Advanced-->Multimedia--> (disabled) Enable Automatic Image Resizing)

hdcomp.jpg
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post #131 of 144 Old 12-26-2006, 08:24 PM
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Quote:
Originally Posted by jacksonian View Post

In my posts as well as the Athens 1080p/720p shootout that was done with DLP projectors (Marantz), it seems that no one can believe the results. And so there's always another factor, whether it be poor source, poor scaling, poor optics, MTF, the need for test wedges, there's always some reason that 1080p *would* have shown an improvement under the right circumstances.

The point I've been trying to make is that in a normal room with normal enthusiast quality equipment and sources, I cannot see any increase in detail between the two. And that is exactly what the 30 or so folks in Greece found.

OK, then let's give your eagle eyes a little test to see how much you know about video and video processing. Take a look at the images in the following link and compare them. Two side by side images with no time lag in between viewing them. Tell me what the differences are between the two.

http://members.home.nl/saen/Special/Zoeken.swf

This challenge is for Jacksonian. For those that see the difference, please don't give it away for him or others.
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post #132 of 144 Old 12-26-2006, 09:05 PM
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Originally Posted by QQQ View Post

This challenge is for Jacksonian. For those that see the difference, please don't give it away for him or others.

I could tell the difference but i wont give it away, d@#kh&%d.
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post #133 of 144 Old 12-26-2006, 09:12 PM
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Wow that's a fascinating comparitive study, really had to peer closely at my LCD to make out the differences.
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post #134 of 144 Old 12-26-2006, 11:04 PM - Thread Starter
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It seems somewhat weird to me that some people still find it hard to believe the validity of Jacksonian's or the Greek's findings, while no one seemed to try to refute the claim made earlier, that state-of-the-art HD-DVD/Blu-ray transfers, have a maximum of 1300 lines of horizontal resolution.

1300 lines of resolution are well in the realm of 720p projectors (1280x720).

Weird.

To me the discussion should not be whether Jacksonian's or the Greek's findings are correct, but whether their findings are limited by the source, or not.

Jacksonian, unlike myself, is not making the claim that if the source material was up to the task, he could still not tell the difference. Jacksonian simply does not know (he can do the same test that I did, and project a high quality digital image, one time using his 1080p projector, and the other time using his 720p projector, and then see if there is a difference. This will put transfer quality out of the equation).
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post #135 of 144 Old 12-27-2006, 12:05 AM
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The test can easily be done using the method I detailed in post #79. I've yet to see anybody refute the test as invalid for any reason. Could it be because it PROVES that there is a detail difference even at 1.5 screen widths (using source material not compromised by storage formats), and nobody wants to admit it?

As far as storage formats go, is there any reason Blu-Ray or HD-DVD can't provide a full 1920 horizontal lines of resolution provided it is given a full 1920x1080 frame not compromized by limited storage formats between the film and the optical media? Once 1080 is prevelant enough I'm sure a studio would swap formats so that they could provide full HD transfers, call it something akin to "superbit" and enjoy a marketing boost from having visibly the best quality transfers, at least until the other studios fall in line.
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post #136 of 144 Old 12-27-2006, 12:24 AM
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You must also remember that a CRT acts differently than a digital device. The CRT for one thing may not be as sharp, in that the transitions between pixels is smoother. This is is almost like a sub-pixel interpolation happening. With a DLP like device, the transitions between pixels are hard edges. You can see these edges and higher resolution is needed to combat them.

Convergence is also not perfect for multi-chip displays. If they can be within a pixel (which many can), having more resolution makes the total convergence error effectively less.
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post #137 of 144 Old 12-27-2006, 03:14 AM
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Quote:
Originally Posted by DanLW View Post

The test can easily be done using the method I detailed in post #79. I've yet to see anybody refute the test as invalid for any reason. Could it be because it PROVES that there is a detail difference even at 1.5 screen widths (using source material not compromised by storage formats), and nobody wants to admit it?

Dan, I'm not sure what those pictures of your blank screens are supposed to prove about anything. Can you please explain?
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post #138 of 144 Old 12-27-2006, 05:27 AM
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Quote:
Originally Posted by Jones_Rush View Post

...no one seemed to try to refute the claim made earlier, that state-of-the-art HD-DVD/Blu-ray transfers, have a maximum of 1300 lines of horizontal resolution.

I read through the source posts and I do not believe the question was ever settled definitively. The 800~1300 lines of horizontal resolution figure for D5 master tapes came from a FAQ written by Joe Kane, as I recall, where he argued that 720p is preferable to 1080i, if memory serves. I don't have time to research this carefully as I am heading out of town in a few minutes and will not be checking this thread for several days. But I invite you to do the necessary legwork in my absence and to post your findings here. You might be able to find the original FAQ on the Joe Kane Productions website.

http://www.videoessentials.com/

I did, however, raise the question again the HD Industry Insiders Thread in the HDTV Software Media Discussion forum. You can follow that line of inquiry here:

http://www.avsforum.com/avs-vb/showt...&&#post9281969

I'll check this thread again when I get back from my trip. Gotta run.

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post #139 of 144 Old 12-27-2006, 07:28 PM
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I'll apologize ahead of time for not reading the entire thread, but just wanted to point out a couple of things. Sorry if they have been covered.

One, we need to be careful when seeing numbers about resolvable horizontal detail to make sure that the numbers aren't "per picture height", but assumed to be absolute, or the other way around.

Second, if a 1920 signal has a unique resolution of 1280 I think a lot of people assume that a 1280x720 projector would then be enough to resolve all of that. But I think that is a false assumption and that a 1280x720 is likely to end up with less real resolution than that from the same signal. In other words a 1920x1080 projector would still resolve more than a 1280x720 projector with all else being equal. Basically, the projector with only 1280 horizontal resolution may end up with an effective resolution of something like 1100 from that signal. Not sure if that one is clear, but basically I think people assume 100% for one case where it isn't 100% for the other (like when looking at MTF values for a 1920 projector). Might be a little bit like comparing street price for one projector to MSRP for another projector when street should be compared to street or MSRP to MSRP.

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post #140 of 144 Old 12-28-2006, 05:55 PM
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Quote:
Originally Posted by jacksonian View Post

Dan, I'm not sure what those pictures of your blank screens are supposed to prove about anything. Can you please explain?

I explained it all in post #79. I think your answer can be found in "Image Explanation". That's the part where I explained how I created the image. If you are not seeing detail differences between the three images...

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Just be sure that your automatic image resizing is off in your internet options. (Tools-->Internet Options-->Advanced-->Multimedia--> (disabled) Enable Automatic Image Resizing)

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post #141 of 144 Old 12-28-2006, 07:28 PM
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From your post 79
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Originally Posted by DanLW View Post

I believe the method I listed above is the best means for everybody on this forum to see for themselves if a 1920x1080 projector will offer any benefit for them. (short of buying three separate projectors) It allows direct comparison of three images of the same physical size and resolution, yet three separate levels of detail roughly equivalent to 480p, 720p, and 1080p.

I can't even comment on your simulation, and I disagree that it is the best way for anyone to determine if 1080p will benefit them.

I have actually purchased a 1080p and 720p projector and put them side by side on the same screen in the same room at the same time with very high quality sources (the best sources any HT enthusiast here would have).

And I could not find any more resolution/detail at any distance from the screen. Why would you rely on a simulation full of confounders when people have actually looked at the projectors (and not just me, but the Athens shootout also)?
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post #142 of 144 Old 12-29-2006, 04:07 AM
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I am in full agreement with jacksonian: To me you have to see it for yourself; theory-based postings are merely interesting IMHO.

In my case, going to 1080p LCD was 80% SDE, 20% slightly more resolution with the best quality video sources. I could have lived with 720p DLP, however my placement options were extremely limited, plus I have found DLP over time a bit fatiguing.

In any regards, as I have said numerous times in this forum, most folks out there would be thrilled with the picture a good $1500 720p projector will produce, assuming they are not bothered by the factors we all know so well.

What is fantastic in my book is now there are 1080p options out there for under $4K where such compromises are not present.
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post #143 of 144 Old 12-29-2006, 10:58 AM
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Originally Posted by DanLW View Post

Does the limitation of the tapes also apply to more recent movies which were recorded digitally, such as the Star Wars movies? Where in the process are these tapes used - between the final cut and the film that makes it's way into theaters, or is it rather something used to get the information to the machines which make the optical media?

Good question. Here, "tapes" generally refers to the 1080/24p master tapes telecined from films and copied for most SD/HD DVDs or broadcasts. (Exceptions, such as older SD master tapes exist.) This discussion arose from Lindahl's earlier post regarding the limits of effective resolution (maximum resolvable detail) on 1080 master tapes--incidently linked in a query by jsaliga in the HD software media discussion forum and answered by HD-DVD insider amirm.

Wouldn't say, from my own ordinary viewings of digitally captured movies, that they differ very much, resolution-wise, from filmed/telecined productions. The 'look' given a production varies greatly with artistic intent and camera filtering (film, video taping ) used. Post production processing, which involves digital manipulation of colors, adding or minimizing the appearance of grain, etc., can radically change images. Digitized productions are then laser scanned to film for most theaters or digitally copied for electronic cinemas.

Early pioneering Star Wars productions, of course, involved blends of computer graphics, some film, and 1920X1080/24p HD cameras. As mentioned earlier above, computer graphics, since it's not sampled, can easily exceed HD resolutions. But the graphics can't look too different from the sampled images, subject to the limiting resolutions that arise when needed anti-aliasing filters are applied.

More recent digitally captured movies use higher-resolution digital-cinema cameras with 35-mm-size sensors. Internal downconversion to roughly 1920X1080 within these cameras from, say, ~4kX2k, means that final captured resolutions come much closer to 1920X1080 than HD sampled only at that standard format resolution (see link above). The limiting resolution, ~1700 lines with standard sampling, is boosted by the oversampling and downconversion. Some major feature film productions are telecined at ~4kX2k and these digital intermediates (D.I.'s), used for post production, also boost effective resolutions after downconversions.

1080 DVDs, as detailed earlier , should deliver more boosted resolutions because of higher bit rates and/or more efficient codecs. But reports so far don't suggest this is commonplace. Movies delivered with HD broadcasts undergo resolution loss with the reduced bit rates (<17 Mbps video payloads). And finally, even though a new 1080p display easily resolves 1920X1080 test patterns, if your STB and/or video source (OTA, DBS, cable) is limiting resolvable details (or reformatting) to <1300 lines, as many report, that's the limit you'll see with motion video. -- John
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post #144 of 144 Old 01-09-2007, 10:42 AM
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I suspect that most people in a dark room will not be able to tell the difference between 720P and 1080p. I have a 115 inch wide 2:35 screen and if I divide this by 1980 I get a pixel size of 1.47 mm. The resolving power of the eye at the center of the field is only one arcmin under Ideal conditions. This gives me a resolving power of about 1.27 mm under Ideal conditions at thecenter of the field and in bright light. Visual acuity drops off rapidly as a funtion of field and is down by 80 percent at 10 degrees and this does not include the effects of color abberations of the eye as the pupil widens in a dark room

I suggest the following double blind experiment. Play a 10 minute segment of a movie througth the same projector at 720P and again at 1080P and have each member of the audience choose when they thought it was played at 720 and when it was played at 1080

My bet is they will not be able tell the difference.
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