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Unless you are standing within 6' away from a 10' HDTV image, I seriously doubt your eyes will be able to pick up the additional details. From any reasonable viewing distance, an HDTV signal is as good as your eyes need.
 

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You guys have a HTPC hooked up for DVD viewing with that setup? I'm sure it'd be fun for those after hour sessions when work activity is low anyway http://www.avsforum.com/ubb/smile.gif


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/frode
 

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Quote:
Unless you are standing within 6' away from a 10' HDTV image, I seriously doubt your eyes will be able to pick up the additional details. From any reasonable viewing distance, an HDTV signal is as good as your eyes need.
I see this all the time. People say with with CD audio too (not needing any improvement).


Try this trick. Watch an HDTV program with a good life-size image of someone's face. Now have someone stand next to the TV and look at the real person's face. Can you see a difference? If you can't, you're probably standing farther away from the image than is a realistic viewing distance.


The idea of HDTV is to have enough resolution to make a large image you can get close to. Until your eyes can be convinced that you're literally looking through a window and not at a video image (close one eye if you want to remove 3-D issues), it has room for improvement.


Yes, your eyes can see the difference between the real person and the image on the HDTV screen.


Myself, I still think it's ludicrous that I can see alising and stair-stepping on basket-ball courts and football fields on 1080I HDTV images. It's not the holy-grail of video people despite the fact that it IS better than 4x3 480I NTSC.


-dave
 

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I've posted this link a couple times before:
http://www.llnl.gov/str/Quinn.html


The above shows one of the visualization theaters at

Lawrence Livermore National Laboratory.


Both the LLNL and Sandia theaters are a result of

ASCI - the Accelerated Strategic Computing Initiative

of the U.S. Dept. of Energy.


Greg
 

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Myself, I still think it's ludicrous that I can see alising and stair-stepping on basket-ball courts and football fields on 1080I HDTV images. It's not the holy-grail of video people despite the fact that it IS better than 4x3 480I NTSC.
That has more to do with the fact that its interlaced than the fact that 1920x1080 is too low a resolution. I don't see much stair stepping at all at my weenie 1280x720p DVD resolution, because its progressive. I think that 1920x1080 is sufficient for quite some time and for quite large screens, its just a matter of getting it in progressive form.


I think, though I couldn't guarantee, that we'd get better results (in terms of your complaints) by getting that HD in progressive (or doubled) form than we would be increasing the existing interlaced format by say %25.


Obviously we ain't gonna get it in progressive form any time soon, so doubling is probably the only solution in the next 5+ years (probably longer of course, but one can always hope :)



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Dean Roddey

The Charmed Quark Controller
[email protected]
www.charmedquark.com


If it don't have a control port, don't buy it!
 

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Sure...that particular artifact of aliasing has more to do with interlace scanning than absolute resolution. But even a 1080P image on a 6 foot screen with the 6:00 news won't look like an actual person standing in front of you from 10 feet away when you have your friend stand right next to the image.


I'm not saying that 720P or 1080P aren't very satisfying video experiences. I was just reacting to the "you wouldn't see a difference" philosophy when, in fact, you would.


In the late 1800's news reporters claimed, in astonishment, that they could not tell the actual voice of the person speaking from the cylinder recording made from that voice. We shouldn't make remarks equally as implausible about our current video technology.


-dave
 

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Go watch an IMAX movie. HDTV looks pretty pittiful next to that. The eye is far from being the limiting factor. Computer monitors generally operate around HDTV resolutions and a 19" monitor at 1024x768 would yield around 75 dpi. A normal laser printer prints at 600 dpi and your eye can see MUCH more detail then that. Magazines can be as high as 2400dpi and they are still a far cry from maxing out our eyes.


The most intresting advance I've read about is a team working on using lasers to print an image directly on the retina. Each eye receives its own image so you all get dimensions. This system is supposed to exceed the resolution of the eye.


Ryan


[This message has been edited by Ryan Pream (edited 07-17-2001).]
 

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Quote:
Originally posted by Ryan Pream:
Go watch an IMAX movie. HDTV looks pretty pittiful next to that. The eye is far from being the limiting factor. Computer monitors generally operate around HDTV resolutions and a 19" monitor at 1024x768 would yield around 75 dpi. A normal laser printer prints at 600 dpi and your eye can see MUCH more detail then that. Magazines can be as high as 2400dpi and they are still a far cry from maxing out our eyes.
The required resolution of an image has to do with the size of the image and the viewing distance. 75 dpi for a monitor is plenty for a viewing distance of 10". 2400 dpi is plenty for viewing even with a magnifying glass. 300 dpi for a photograph is more than sufficient for a photograph. HDTV is plenty for a 60" image from 6' away. You get to the point of diminishing return by going beyond that. I don't see any practical application for the home market beyond HDTV. Scientific and medical applications are a different story.
 

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If people are complaining about bulb replacement costs now, imagine replacing a dozen at a time. http://www.avsforum.com/ubb/eek.gif


A wise statement in the article notes that the resolution limitation is reached with the viewers eyes, rather than the limitations of the super-resolution display (although they are still planning on building a higher resolution model) http://www.avsforum.com/ubb/rolleyes.gif


I think that one JVC QXGA display would easily provide a bright, crisp image at 2048 X 1536p that would be virtually indiscernable from the mega-complex, multi-projector setup shown, when viewed from 8+ feet away.


Ryan,


High resolution photography looks great, but it's usually viewed on a small piece of paper at much less than an arm's length away from the viewer.


I enjoy watching IMAX shows for the immersive environment, but I often notice the film's grainy texture, jittering, and debris. And I feel that my much lower resolution projector and much smaller screen looks more clear and detailed with a 1080i HD feed than some IMAX film presentations that I've seen.


Sometimes having the best specs is not the ultimate judgement of superiority. Likewise, having an mondo audio system that whose "superior" output can only be discerned by dogs and bats is overkill for anyone but the most fervent audiophiles.


The question that needs to be asked isn't if a higher resolution display is possible through complex technology, but if it is necessary.


Not that I don't love the technology, but does the application demand it if the screen will be viewed from 10 feet away?


-Dean.
 

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Granted distance is key. But we are so far from perfect visual reproduction compared with audio. A high end audio system is perhaps 90% of the way to reality. A high end video system is perhaps 10% of the way there. When your eyes can't tell the difference between reality and the "holodeck" you are in we will be there.


Ryan

 

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Quote:
The required resolution of an image has to do with the size of the image and the viewing distance. 75 dpi for a monitor is plenty for a viewing distance of 10". 2400 dpi is plenty for viewing even with a magnifying glass. 300 dpi for a photograph is more than sufficient for a photograph. HDTV is plenty for a 60" image from 6' away. You get to the point of diminishing return by going beyond that. I don't see any practical application for the home market beyond HDTV. Scientific and medical applications are a different story
I disagree. The needs of military/scientific/medical simulation are different from those of the home theater audience (and film directors).


The simulation audience is SUPPOSED to be aware that it’s a simulation. A doctor working with a teleoperator system on your heart, had better be aware that he’s manipulating a remote tool instead of working an actual scalpel by hand. And no chemist working in molecular synthesis is going to believe that his data glove is actually touching molecules.


But the home theater (and commercial theater) audience is different. Theater is about suspension of disbelief. That means a display technology that can match or exceed the eye’s resolution (with one eye closed, if it isn’t true 3D). You need to be able to see THROUGH the display, and believe you’re looking at a real scene. Dave’s suggestion of a “Turing Test†for video displays is right on the mark.


What we’re looking for (and I mean the creative/production side as well as the audience), is nothing less than Greek Theater; real people standing in front of you, but with the 21st Century addition of time manipulation, change of perspective, full control over ambient lighting, and CGI whenever you need it to make a dramatic point. That’s what contemporary filmmakers and the audience all want. That's what we've wanted ever since the days of Homer. We’re just waiting for the technology to catch up.


Audio is there right now. Okay, we can argue about it... but it’s pretty damned close. Video isn’t there yet, by a long shot. HDTV is going to look like black and white ‘50’s television when the real thing arrives. Does anyone here seriously think that the evolution of major "motion picture" theatrical releases, or video production, is actually going to stop at 35mm, 70mm, IMAX, or HDTV? I may not live to see it, but I'm pretty sure it doesn't stop here. http://www.avsforum.com/ubb/smile.gif


P.S. this isn’t intended to denigrate the original post. The Sandia Labs setup is a cool system, relative to what consumers can buy now. I’d love to have it in my house. But I suspect that while the pixel resolution is high, the colorspace is probably not deep enough, or accurate enough, to make me believe that a real person is standing in front of me (with one eye closed). True color and contrast accuracy isn't a strong requirement in the simulation field. If anyone wants to front me a plane ticket, cab fare, and access to that display, I’d be glad to be proven wrong. http://www.avsforum.com/ubb/smile.gif


P.P.S. the laser raster system projecting into the retina sounds like a cool idea. But it’s a one-person, headset display (as far as I can tell). We need something that recreates campfire story telling... several people sharing the experience in a room. That’s why home theater is such a powerful experience, and why (aside from technology problems) "VR" headsets never took off in the consumer market. We also need a display technology where the cost doesn’t escalate with the number of people using it.



[This message has been edited by foldedpath (edited 07-17-2001).]
 

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Ryan,


I disagree with the assessment that video is relatively 10% towards the perception of reality.


I think that the biggest limitation towards thinking that you actually see something real in front of you is the lack of true 3-D imaging, and not so much resolution.


I think that if you got two G90s and had them setup to alternate-image a native 1080p scene in 3-D onto a 5 foot wide high resolution diffusion screen and set up an aquarium scene, or an interior view and had observers walk by seeing it as a window, that many people wouldn't know that it wasn't real.


That would seem to indicate that we could be more like 60-70% there with today's technology visually. Admittedly, this is not the picture quality that an average viewer will see with a VHS tape deck and 19" color TV, but I think that HD resolution is starting to get much closer to our visual acuity level, only lacking 3-D to bridge the believability gap.


Sure 40K X 30K resolution with 5000:1 contrast would certainly help to make a picture look more real, but I'd be pleased to get my prerecorded movies in 1080i/p form, 3-D would be icing on the cake.


-Dean.
 

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The other day someone in our church brought slides back from their trip to the rain-forest.


We dug out a slide-projector and projected the images onto a white wall. We were sitting about 15' away and the image produced was only about 5 feet wide.


The level of detail and realism was jaw-droppingly astonishing. Those of you who complain about the artifacts in "film"...please be aware you're really talking about bad-multigeneration film processing and poor film-stock...not the medium itself.


The image on the wall was dramatically sharper, clearer, naturally colored and seemingly infinitely detailed and made the very best HDTV images look a bit lacking.


REALLY.


Like I said. You think that 1080P is so great on a 6 foot screen sitting 10 feet away? Have your friend stand next the picture and just look at the difference between the detail in real-life and what you're seeing on the screen.


Holding a good-quality photograph next to your computer screen with a digital capture of the same...even from several feet back...will show you what I mean.


Or go look out your window and stare at the trees across the street. See how you can see individual leaves and micro-detail? Now go and look at your HDTV. It doesn't matter how far or close you sit...it's not quite the same.


Does that mean that 1080P won't make me and you happy? It just might. But that's not the same as saying that our human eyes aren't capable of perceiving any more detail than it can give us.


-dave
 

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Dave,


I'm not at all surprized that a 4,000 X 2000 resolution slide image viewed on a 5' screen from 15' away would look stunning.


My point is if you had that same slide digitally scanned at 1920 X 1080 resolution and projected it onto the same 5' wide screen with a calibrated G90 @72Hz from a computer, that half of the viewers would either prefer the FPTV, or not notice the difference.


What I'm talking about is a point of diminishing returns for practical use.


Current 1080i HD is interlaced and the image is compressed 40 to 1. I've seen movies in a local E-Cinema theater with 4 to 1 compression and only 1280 X 1024p resolution displayed on a 50' wide screen and it looks as good or better than most theatrical film presentations that I've seen.


I'm actually amazed at how good 720 X 480p DVDs look scaled up to 1360 X 1024 on a 13' wide screen.


Don't get me wrong. There is certainly room for improvement, and I'm looking forward to the day when I've got may native 1920 X 1080 resolution projector at home with a zero compression 1080p source playing (maybe even 3-D). But what I'm seeing is closer to real life than 10% with even 1080i material.


-Dean.
 

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Quote:
My point is if you had that same slide digitally scanned at 1920 X 1080 resolution and projected it onto the same 5' wide screen with a calibrated G90 @72Hz from a computer, that half of the viewers would either prefer the FPTV, or not notice the difference.
My point was that looking at that image at that size on that wall looked clearly superior to looking at any HDTV image that same size from that same distance. It was simply clearly better than any video image I have ever seen...indicating that the "diminishing return" issue has yet to be exhausted with the current HDTV standard.
Quote:
Current 1080i HD is interlaced and the image is compressed 40 to 1. I've seen movies in a local E-Cinema theater with 4 to 1 compression and only 1280 X 1024p resolution displayed on a 50' wide screen and it looks as good or better than most theatrical film presentations that I've seen.
True, 1080P is better than 1080I, and less compression is better than more. Of course, I'd also point out that the "film" we experience in the average movie house is also not the bench-mark of quality the medium is capable of delivering. In fact, just looking at the spectacular quality of a single 35mm slide (which is the original negative) makes it clear just how much the degredation occurs in the processing and multi-generation steps involved between what goes on the film in the camera and what ends up on the big-screen at our local movie house. So e-cinema isn't an apples-for-apples comparison either.

Quote:
I'm actually amazed at how good 720 X 480p DVDs look scaled up to 1360 X 1024 on a 13' wide screen.
I long to share that experience...not because I don't believe that you're amazed...but because I'm trying to save up for my projector and (maybe) HTPC!! What's your equipment?

Quote:
Don't get me wrong. There is certainly room for improvement, and I'm looking forward to the day when I've got may native 1920 X 1080 resolution projector at home with a zero compression 1080p source playing (maybe even 3-D). But what I'm seeing is closer to real life than 10% with even 1080i material.
That's my dream too. FMD-HD images with 1080P resolution and minimal video compression...with 7.1 DSD or 24/192 soundtracks (uncompressed). Ahhh...


Of course, as good as it will be, it probably would still be possible to tell the difference between looking at the projected image of a reference 1920x1080P image vs looking directly at the real thing.


The subjective question...as is the case with high-end audio...isn't whether or not there's really a difference so much as it is how important that difference is to a particular individual and how much are they willing to spend to acheive it.


-dave



[This message has been edited by DaViD Boulet (edited 07-18-2001).]
 

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Being a great high resolution medium, slide picture quality is a great goal to shoot for in picture clarity.

Of course adding motion (and someday 3-D) bring elements of realism that still photos cannot. And the other side of that coin is that slides vivid clarity is unreachable today in motion picture/video.


But HD is getting VERY good, and a good DVD transfer can easily suck you into the picture, as if you were there, even though the resolution is severely lacking relative to super-high resolution images.


My setup is:
http://www.hometheaterforum.com/bbs/...ent/21117.html


We are actually in agreement on what we see, and what we want. You are just focusing (clearly) http://www.avsforum.com/ubb/wink.gif on the best target goal of our unimpared eyesight, and I'm bringing up how far that we have come toward that goal of lifelike realism with today's (and tomorrow's) technology.


-Dean.
 
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