8K by 4K or Octo HD - the real SUHDTV technology - Page 7 - AVS Forum
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post #181 of 676 Old 09-21-2012, 12:37 PM
 
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NHK set a 2020 target date for public broadcasts to begin in Japan but according to Dr Kubota, recent progress means that they are “already talking about moving the target date forward as soon as possible.”

He later confirmed to TrustedReviews that its new target date could be only four years away. “The speed of technological innovation is very fast now. I would be very happy if we could make it around 2016,” said Dr Kubota.

Other broadcasters, such as the BBC, are free to develop Ultra HDTV on their own timescale. However, it’s hoped that there won’t be the long gap between this new format’s Japanese launch and a take-up in other countries; unlike conventional HDTV, which took ages to reach the UK. Satellite operator SES-Astra has already hinted that the capacity exists for the 4K (3,860 x 2,160 pixel) version of Ultra HDTV to start in Europe within three years.

http://www.trustedreviews.com/news/nhk-s-super-hi-vision-plans-could-bring-ultra-hdtv-as-soon-as-2016
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post #182 of 676 Old 09-21-2012, 12:38 PM
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Originally Posted by Lee Stewart View Post

Except it specifically says 24 Gbps uncompressed and 280 Mbps compressed, so your guess is incorrect.
(7,680×4,320) x 3 x 30 x 8 = 23.9Gbs - Bingo! They are doing 8Kp30 at 8 bit color depth. So they are going to have to quadruple their frame rates and double their color depth to meet their own promises.

That article went on and on about the computer power required to do this. Now remember that what they are promising is 8x more intensive. And they think they can deploy this to the consumer in 8 years. rolleyes.gif
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post #183 of 676 Old 09-21-2012, 12:41 PM
 
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Originally Posted by mcnabney View Post

(7,680×4,320) x 3 x 30 x 8 = 23.9Gbs - Bingo! They are doing 8Kp30 at 8 bit color depth. So they are going to have to quadruple their frame rates and double their color depth to meet their own promises.
That article went on and on about the computer power required to do this. Now remember that what they are promising is 8x more intensive. And they think they can deploy this to the consumer in 8 years. rolleyes.gif

Don't you get the same result when you substitue 25 fps and 10 bit color depth?

BTW - if you read the article above your post, NHK is now saying they think they can deliver 8K in 4 years.
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post #184 of 676 Old 09-21-2012, 01:08 PM
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Originally Posted by Lee Stewart View Post

Don't you get the same result when you substitue 25 fps and 10 bit color depth?
BTW - if you read the article above your post, NHK is now saying they think they can deliver 8K in 4 years.

Into Movie Theaters.

Remember, their standard includes 22.2 channel audio too. They are trying to beat RED to be the camera/projector provider for digital cinema that can actually reproduce 70mm/IMAX quality for events. This is not going into the homes of regular consumers since it requires a really big screen. That doesn't mean there won't be some rich guys installing them in their mansions. Those same people also own medium-sized jets. Everyone just needs to get over 8K in the home. Seeing it in the theater might actually make it worth braving the masses at the cineplex.

4K is the real deal. It can provide the current cinema resolution in the home. It can fit on quadruple layer BluRays (which new players are beginning to support). It is ideal for 60-150" screens - which homes can have. Combined with the latest compression there is even some chance of getting pay-TV providers to provide a few channels of it. And most notably - most previously filmed content can get their highest quality scan at this resolution. That means when you buy Lord of Rings @4K you know that you have the maximum level of detail. They will have to remake the movie to get higher.

My actual fear is that people and companies will balk at 4K right now because they think they will need to go to 8K. The market needs to acknowledge that 8K isn't a consumer technology and focus on 4K in the here and now.
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post #185 of 676 Old 09-21-2012, 01:16 PM
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Originally Posted by Lee Stewart View Post

substitue 25 fps and 10 bit color depth?

No, that gets 24.9. And would also be really stupid. This is the Olympics - which by definition involve lots of motion. Some very rapid motion. 30fps seriously sucks for sports. Hell, I bet a 4K display at 120fps and 10 bit color would actually look a lot better to the viewer. I know from experience that 720p60 looks better than 1080p30 at sporting events.
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post #186 of 676 Old 09-21-2012, 01:25 PM
 
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Originally Posted by mcnabney View Post

Into Movie Theaters.

It doesn't specifically say that does it?
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Remember, their standard includes 22.2 channel audio too. They are trying to beat RED to be the camera/projector provider for digital cinema that can actually reproduce 70mm/IMAX quality for events.

Trying to beat Red? They already did. Red has shown no 8K camera in fully working condition in a real environment.
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This is not going into the homes of regular consumers since it requires a really big screen. That doesn't mean there won't be some rich guys installing them in their mansions. Those same people also own medium-sized jets. Everyone just needs to get over 8K in the home. Seeing it in the theater might actually make it worth braving the masses at the cineplex.

Sharp showed an 85" SHV display. That is one inch larger than the LG/Sony 4K TVs that will go on sale this year.
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4K is the real deal. It can provide the current cinema resolution in the home. It can fit on quadruple layer BluRays (which new players are beginning to support).

It''s so easy to say . . . 4 layer BDs. But in reality the manufacturing of such a BD-ROM has never been done before. No one knows the yield rate will be. No one knows the reliability rate when it comes to mass produced players. Sorry - BDXLs are not the same as BD-ROMs when it comes to manufacturing. They are BD-Rs not BD-ROMs
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It is ideal for 60-150" screens - which homes can have. Combined with the latest compression there is even some chance of getting pay-TV providers to provide a few channels of it. And most notably - most previously filmed content can get their highest quality scan at this resolution. That means when you buy Lord of Rings @4K you know that you have the maximum level of detail. They will have to remake the movie to get higher.
My actual fear is that people and companies will balk at 4K right now because they think they will need to go to 8K. The market needs to acknowledge that 8K isn't a consumer technology and focus on 4K in the here and now.

8K will do nicely on your 60" to 150" sized displays. They will be selling 4K TVs without any 4K content. The idea is to upscale HD to 4K. Same thiing can be done with 8K until content is made available.

4K is nothing more than a way station on the road to what many feel is the final stop . . . 8K
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post #187 of 676 Old 09-21-2012, 01:31 PM
 
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Originally Posted by mcnabney View Post

No, that gets 24.9. And would also be really stupid. This is the Olympics - which by definition involve lots of motion. Some very rapid motion. 30fps seriously sucks for sports. Hell, I bet a 4K display at 120fps and 10 bit color would actually look a lot better to the viewer. I know from experience that 720p60 looks better than 1080p30 at sporting events.

Except your 6 bit color depth isn't part of the SVH specs. And you keep forgettng the demos were done in the UK. They don't use 24 and 60 Hz due to their 220V power. They use 25 and 50 Hz.

24.9 Gbps is close enough to the stated 24 Gbps in the article.
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post #188 of 676 Old 09-21-2012, 02:01 PM
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Originally Posted by mcnabney View Post

1. NHK wants to sell 8K cameras to compete with REDs pending 8K cameras. There is a use for that resolution in theaters and specialty situations - not in the home. Trust me, NHK will backtrack and soon start talking about their 4K options in the consumer segment.
This si utterly rubbish!

First of all; NHK is a the governmental owned TV station in Japan, like BBC is for the UK.
They don't manufacture and sell equipment.

The newest 8K CMOS Broadcast cameras (one big and one smaller) NHK used at the London Olympics where built by Hitatchi.
RED announced a 9K 645 (medium format) digital film camera in 2008, as a part of their future timeline. Since then they have not mentioned it with a word except saying it will be made at some time in the future.

Broadcast cameras and and digital cinema cameras are two very different technologies. Digital cinema cameras can not be used for broadcast at their native resolution and broadcast cameras can not be used for digital cinema because of the image process in camera. The main 8K camera NHK used in London is a big beast of a camera, totally unusable for modern cinema production.

Pansonic (145" 8K plasma), Sharp (85" 8K LCD) and JVC ("8K" E-Shift Lcos projector) build the displays NHK use in their UHDTV tests.

Try not to post scenarios that you have dreamt up in your head that will only exist there and nowhere else.



8K UHDTV: How do you send a 48Gbps TV signal over terrestrial airwaves?
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post #189 of 676 Old 09-21-2012, 02:49 PM
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Originally Posted by mcnabney View Post

Human visual acuity of 1 arcminute is standard knowledge. 20/20 vision is by definition the ability to distinguish 1 arcminute. Just because some people have 20/10 vision doesn't mean 20/20 isn't the standard.
I'm going to send you here for the second time. While you're there, you can visit here for some extra information about average acuity (by Snellen).

This time, come back with an argument. It would be embarrassing if I had to correct you every time you claim this.
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post #190 of 676 Old 09-21-2012, 07:48 PM
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@Owen - simulation is simulation. Physical pixel structure is different on simulated images and on real lower-resolution display. Why haven't you used nearest neighbor for upscaling, like this:

Good idea, nearest neighbor is very sharp but a little harsh.
Here are the same images using nearest neighbor.
For me all the images look effectively identical at the equivalent of 1.5x full picture height and since thats an impractically distance for movie viewing I dont see much point in 8k as a display format.
Video looks a lot better than a still image so small differences will never be noticeable.

View at 10 times image height to simulate full image at 1x picture height.
8kv4ktest4.jpg


View at 5 times image height to simulate full image at 1x picture height.
8kv4ktest3.jpg
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post #191 of 676 Old 09-21-2012, 08:14 PM
 
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Here is some additional specs on NHKs new 8K camera:
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NHK's 3rd-generation 8K prototype camera, for example, is limited to one hour of filming. That's how fast its dual banks of 16 × 64 GB P2 cards fill to their terabyte capacity. The camera's 1.5-inch CMOS sensor captures 33.2MP footage shot at 120fps—that's roughly 4 billion pixels per second of data, moving at a rate of 51.2 GB per second, sychronously transmitted on 96 channels. The resolution is so high that focus isn't even controlled by the cameraman. Viewfinders currently don't have a resolution greater than 1K, so the cameraman can't know if the shot is actually in focus, so the job is handled by a remote CCU operator.

http://gizmodo.com/5944270/how-4k-tv-works
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post #192 of 676 Old 09-21-2012, 08:22 PM
 
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Earlier this year Japan public broadcaster NHK had also succesfully transmitted 7,680 x 4,320 video using terrestrial transmission technology.

NHK has developed a high-capacity transmission technology for the next-generation broadcasting system and conducted successful field tests in which the signal was transmitted using two channels (UHF31, 34) at a bit rate of 183.6Mbps and it was correctly received at a distance of 4.2km. "

http://www.avsforum.com/t/1428971/4k-bluray-seems-closer
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post #193 of 676 Old 09-21-2012, 09:12 PM
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Originally Posted by coolscan View Post

You must distinguish between capture (film&digital) and delivery after post production.
Both film and digital capture format have low contrast regardless of resolution to capture as much dynamic range as possible.
Desired contrast and electronic sharpness is then added in post.

I agree that high contrast increase the perceived sharpness.
Low resolution, f.ex. 2K capture requires more added electronic sharpness added in post than capture done at a higher resolution.
5K or 6K capture for 4K or 2K delivery will have a higher organic sharpness and avoids the Edge Enhancement that we so often see in movies released on BD.
The reason for this EE is that previously one thought that 2K film scans and 2K cameras was sufficient for 2K delivery. When the material is authored for BD, the production people deem the material to be "too soft" and over-sharpens the material.
Now one has learn that film schould be scanned at 4K for 2K delivery and at least at 6K for 4K delivery.
The same with digital cameras that now have gotten sensors with higher than 2K resolution for 2K delivery.
That those cameras also will be used for up-converting to 4K delivery just show how little quality consciousness and care for image quality there are in the movie industry.
What I see complained about from people that work in the industry is that there are mostly stupidity, hearsay, fanboyism, incompetence and money that is the reason for choosing a capture format for a movie.
The choice of equipment based on the desire for the best technical Image quality capture and "future proofing" are more rare.
The 2K digital cameras does a lot of in camera processing (including electronic sharpening) before the images are stored on the capture cards/tapes.
This processing doesn't happen for 35mm film before post production stages.
That' why the 2K cameras can look sharper.
Similar to the 35mm film format happens to the digital RAW capture formats on those cameras that doesn't pre-process the RAW in camera.
Stating as you do; Have you seen much movies shot on Sony F65 (6K'ish) or Red Epic(5K) RAW properly processed, or film scanned at 6K, projected with the latest Barco or Christie Series-2 4K projectors (Sony 4K SXRD/Lcos is softer)?
I don't see the evidence at all in your estimates, because you forget an important point.
That is that IMAX titles usually are scanned at 8K and down-sampled to 2K.
Which shows that very high resolution capture matters very much compared to 2K capture.
By the way; Estimates done for 35mm capture film (not release prints) is that it has from 1.5 to 4 megapixel resolution, depending on type of film used and shooting situation.



As consumers we only care about the delivery format, the pixel count of the capture system is a secondary issue.
MTF and dynamic range are completely separate issues. MTF quantifies the amplitude v frequency response of the system not the overall dynamic range.
All digital capture systems have a falling high frequency response that must drop close to zero at nyquist (spatial frequency equal to the pixel grid) to avoid out of band frequencies entering the system and causing distortion. The low pass filters used (both optical and digital) cannot have an infinite cut off, capturing with many more pixels than is required for final output allows better filter performance and higher in band response when scaling down to the lower output resolution.

Lenses, film and film scanners also have an MTF response (falling high frequency response) and the final output is the sum of all MTF losses in the chain. With digital cameras the additional losses of film are avoided which allows higher mid band MTF which is what defines a sharp picture.
No matter what capture system is used a digital image can only have about 60% of the visible resolution its pixel count would suggest, above that MTF is too low for detail to be visible.

The reason IMAX or high res digital looks sharper than 35mm film when encoded to 2k is because mid frequency MTF (well below 2k) is higher, the limiting resolution is the same in all cases and set by the 2k format.
Since most 35mm film titles are significantly softer than IMAX or high res digital when encoded to 2k its clear the 2k format is not the major limitation for 35mm film source.
"Resolution" and image sharpness are separate issues. A high resolution image with low MTF will look soft while a lower resolution image with high MTF will look sharp. High resolution without high MTF is pointless for movies.

I am all for high res capture systems as they do offer tangible befits, the issue here is 8k v 4k as a display format and I just dont see 8k being worth it for reasonable screen size to viewing distance ratios. A 200" diagonal screen at 8' is not reasonable or practical IMHO.


Here is an example of what falling MTF at high spatial frequencies does to visible resolution. The top half is 100% MTF (perfect), the lower half is a typical representation of the performance of a digital capture system, at the pixel limit (nyquist) MTF drops to about 10%. The limiting "resolution" is the same in both cases as you can see the fine detail if you look closely, but stand back from the screen and the resolution you can actually see changes dramatically.

Remember, most details in the real world dont have 100% relative contrast to begin with, 30% is likely more typical. Factor in 50% or more MTF loss and a 30% contrast difference between details in the original image becomes 15% or less in the video which is useless.
mtfcurveproviasine.jpg


For those who want a better understanding of "MTF" I suggest this tutorial.
http://www.normankoren.com/Tutorials/MTF.html
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post #194 of 676 Old 09-21-2012, 09:56 PM
 
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Originally Posted by Owen View Post

I am all for high res capture systems as they do offer tangible befits, the issue here is 8k v 4k as a display format and I just dont see 8k being worth it for reasonable screen size to viewing distance ratios. A 200" diagonal screen at 8' is not reasonable or practical IMHO.

But an 85" 8K diagonal display at 6' is both reasonable and practical.

BTW - thanks for the info. Very informative.
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post #195 of 676 Old 09-21-2012, 10:12 PM
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Originally Posted by Lee Stewart View Post

But an 85" 8K diagonal display at 6' is both reasonable and practical.
BTW - thanks for the info. Very informative.

That's only 54 degree viewing angle, barely enough for 4k which is good to 60 degrees plus. 8k needs 120 degrees plus, thats like viewing the 85" from 3'.
85" at 6' is 1.7x image height, if you can see a difference between 4k and 8k at that distance you have exceptional vision. Look at the images I posted above, view the small one at 17 times its height and large one at 8.5 times to get 1.7x effective full picture height performance.

How do you get good sound integration at that distance, even at 10' its difficult.

Glad to be of assistance.
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post #196 of 676 Old 09-21-2012, 10:36 PM
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Quote:
Originally Posted by 'mcnabney" 
(7,680×4,320) x 3 x 30 x 8 = 23.9Gbs - Bingo! They are doing 8Kp30 at 8 bit color depth
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Originally Posted by Lee Stewart View Post

Except your 6 bit color depth isn't part of the SVH specs. And you keep forgettng the demos were done in the UK. They don't use 24 and 60 Hz due to their 220V power. They use 25 and 50 Hz.
24.9 Gbps is close enough to the stated 24 Gbps in the article.
For the SHV Olympics demos (that were done in the UK - using NHK's cameras), they used 60 fps.

http://www.engadget.com/2012/07/31/super-hi-vision-eyes-on
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with 60 progressive frames per second
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post #197 of 676 Old 09-21-2012, 10:39 PM
 
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Originally Posted by Owen View Post

That's only 63 degree viewing angle, fine for 4k but no good for 8k.

IMO, the "recommended" 100 degree viewing angle for 8K is based on very large screens (300+inches). Do I think people are going to sit 3 feet from an 84" 8K display to reach the 100 degree viewing angle? No. I do not. Nor do I believe you will lose seeing the extra resolution 8K provides over 4K by sitting back 6 feet from that size of a display. It's just too short of a distance.
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How do you get good sound integration at that distance, even at 10' its difficult.

I don't see the problem. Just use smaller "screen channel" speakers aimed a bit towards the "sweet spot" seat. It's only an 84" image. It doesn't need a sound system suited for a 200" image.
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post #198 of 676 Old 09-21-2012, 10:42 PM
 
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Originally Posted by Joe Bloggs View Post

For the SHV demos (that were done in the UK), they used 60 fps.

OK - thanks for that. So somewhere there is a math error (mcnabney's formula?) because they sure weren't using 3 bit color depth. biggrin.gif

Joe - did you see one of the 8K demos during the Olympics?
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post #199 of 676 Old 09-21-2012, 10:48 PM
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Originally Posted by Lee Stewart View Post

OK - thanks for that. So somewhere there is a math error (mcnabney's formula?) because they sure weren't using 3 bit color depth. biggrin.gif
I'm guessing his calculation assumes RGB colour, and not something like 4:2:0 colour or whatever chroma subsampling they used

edit: here's another article link
http://www.tvtechnology.com/article/broadcasters-show-the-big-picture-from-the-olympics/214799
"Production begins with the acquisition of content on NHK prototype Super Hi-Vision cameras, at 48 Gbps"

(and the BBC article says uncompressed at 24 Gbit/s)
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Joe - did you see one of the 8K demos during the Olympics?
No frown.gif
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post #200 of 676 Old 09-21-2012, 11:17 PM
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Originally Posted by Lee Stewart View Post

IMO, the "recommended" 100 degree viewing angle for 8K is based on very large screens (300+inches). Do I think people are going to sit 3 feet from an 84" 8K display to reach the 100 degree viewing angle? No. I do not. Nor do I believe you will lose seeing the extra resolution 8K provides over 4K by sitting back 6 feet from that size of a display. It's just too short of a distance.
I don't see the problem. Just use smaller "screen channel" speakers aimed a bit towards the "sweet spot" seat. It's only an 84" image. It doesn't need a sound system suited for a 200" image.

I corrected my previous post, it now reads.
"That's only 54 degree viewing angle, barely enough for 4k which is good to 60 degrees plus. 8k needs 120 degrees plus, thats like viewing the 85" from 3'.
85" at 6' is 1.7x image height, if you can see a difference between 4k and 8k at that distance you have exceptional vision. Look at the images I posted above, view the small one at 17 times its height and large one at 8.5 times to get 1.7x effective full picture height performance."
Remember, you are very unlikely to ever get video as sharp as a still photo and differences that are visible in stills wont be in video.


I have owned a 70" TV for over 5 years and the sound situation is not as simple as you think.
A much larger screen viewed from 10' or more works much better, thats why I have a projector.
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post #201 of 676 Old 09-22-2012, 12:21 AM
 
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Quote:
Originally Posted by Owen View Post

I corrected my previous post, it now reads.
"That's only 54 degree viewing angle, barely enough for 4k which is good to 60 degrees plus. 8k needs 120 degrees plus, thats like viewing the 85" from 3'.
85" at 6' is 1.7x image height, if you can see a difference between 4k and 8k at that distance you have exceptional vision. Look at the images I posted above, view the small one at 17 times its height and large one at 8.5 times to get 1.7x effective full picture height performance."

That is the first time I have ever heard that 8K requires 120 degrees plus. I am going from this on optimum viewing angles:

shv.gif

And like I said, those viewing angles are not "cast in concrete." They are considered "optoimum" for large displays. Just like there are "optimum" seats in a commerical movie theater - maybe 25% of all seats. The other 75% are either too close, too far or too off-center. But they still sell out theaters don't they?

BTW - there are no Seating Distance Police. biggrin.gif

I looked at your images above. Not sure I looked at them properly though. I zoomed my display (20") to 300%. The apartments - the 8K were still viewable with no artifacts while the 4K version was a total mess. All pixelated and blocky. As far as the woman's face, there was little difference between them and IMO, has to do with such a closeup type photo.
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Remember, you are very unlikely to ever get video as sharp as a still photo and differences that are visible in stills wont be in video.
I have owned a 70" TV for over 5 years and the sound situation is not as simple as you think.
A much larger screen viewed from 10' or more works much better, thats why I have a projector.

I have owned numerous HT setups, all with multichannel sound setups. From 27" all the way up to 144." The biggest mistake I see that many people make is having a sound system that is bigger than their display. If you can't design the sound system to match both the size of the display and sweet spot seat, then you need to do a lot more research.
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post #202 of 676 Old 09-22-2012, 02:18 AM
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30 degrees is normally considered the correct distance for 1080 (2k) therefore 4k=60 degrees and 8k= 120 degrees. Whoever made that diagram you posted cant add up, double 30 is not 55.
I have tested my vision many times over the years and when viewing test patterns with 100% MTF my eyes conform well with what is considered normal visual acuity. Obviously some people have better vision than others but who wants to spend their time looking at test patterns?
When viewing real video content that will never have 100% MTF at high spatial frequencies no matter how many pixels it uses the limits are lower. In fact the higher we go in resolution the lower MTF becomes as lens performance becomes a limiting factor at very high spatial frequencies.
Remember resolution without high MTF is invisible.

As for the sound issue, I agree its important the sound match the picture, big sound with a small picture is not ideal and the reverse is also true
Having said that the brain can easily tell the difference between an 85" viewed from 6' and a 170" viewed from 12 ', the viewing angle is the same but the viewing experience is not. The same goes for sound, near field listening at 6' is different to 12'.

I would sit 12 from a 170" screen but not 6' from a 85", others may feel differentially, thats their choice.

Quote:
Originally Posted by Lee Stewart View Post

I looked at your images above. Not sure I looked at them properly though. I zoomed my display (20") to 300%. The apartments - the 8K were still viewable with no artifacts while the 4K version was a total mess. All pixelated and blocky. As far as the woman's face, there was little difference between them and IMO, has to do with such a closeup type photo.

No you are definitely not looking at them properly. Zooming to 300% is liking looking at you projector screen though a set of binoculars, its silly.
Follow the instruction I gave. Display the images 1:1 (download them and load in photo editor to be sure you have 1:1). Then measure the height of the small image on screen and view the image from 10 times that distance to see what a 8k and 4k image looks like when viewed at 1 times picture height or about 84 degrees viewing angle, closer then just about anyone would ever want to sit.. Remember the full image is 10 times larger and wont fit on just about any PC monitor so a crop is used.

The larger image must be viewed from 5 times its height because it is twice as large. If it wont fit at 1:1 (100%) on the monitor at cant really be used.

Double the above distances if you want to see what 2 times image height looks like (about 42 degrees viewing angle), most people find even that too much for comfort. Its like viewing an 85" screen from 8'.

Anyone who can tell 8k from 4k at 2x picture height (42 degrees) deserves to win a prize.
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post #203 of 676 Old 09-22-2012, 04:15 AM
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First thing's first. Mathematically, you get wrong result if you do this: perfect number of degrees = number of pixels / number of pixels per degree (related to visual acuity). Why? Because display is flat and not a hemisphere where every part of display is located at the same distance from eyes. Please don't do this. Example: 7680/110 = 69.81. Wrong.

Now for acuity. If you are conducting tests yourself, you have to have a sufficient contrast. Acuity depends on contrast too. Also, you have to use nearest neighbor algorithm. Yes, it's harsh but that's the way real lower-resolution display works.

Wrong way of simulating [angular] resolution:
wrongway.png
View at 100%.

Right way of simulating [angular] resolution:
rightway.png
View at 100%.

From NHK:


Average acuities of participants are next:


Therefore, NHK concludes that most of the benefit for average consumer will be seen up to [angular resolution of] ~110 pixels per degree. (Not 60 ppd as 20/20 would suggest, by the way 20/20 isn't even average acuity).

Two very important questions:

  1. Will effective acuity be higher in the future due to very high-contrast displays making today's calculations obsolete? Very likely.
  2. Will results of the tests conducted with real double-density displays yield different results than results we have today (simulated resolution)? Very likely.
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post #204 of 676 Old 09-22-2012, 06:39 AM
 
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Quote:
Originally Posted by Owen View Post

30 degrees is normally considered the correct distance for 1080 (2k) therefore 4k=60 degrees and 8k= 120 degrees. Whoever made that diagram you posted cant add up, double 30 is not 55.

Sorry - the diagram is correct, it is you that is wrong. Right from JBC:

SHVVA_zps5132ca47.jpg
Quote:
I have tested my vision many times over the years and when viewing test patterns with 100% MTF my eyes conform well with what is considered normal visual acuity. Obviously some people have better vision than others but who wants to spend their time looking at test patterns?
When viewing real video content that will never have 100% MTF at high spatial frequencies no matter how many pixels it uses the limits are lower. In fact the higher we go in resolution the lower MTF becomes as lens performance becomes a limiting factor at very high spatial frequencies.
Remember resolution without high MTF is invisible.

Did you see any of the 2012 Olympics demos of 8K in London or Wash. DC?
Quote:
As for the sound issue, I agree its important the sound match the picture, big sound with a small picture is not ideal and the reverse is also true
Having said that the brain can easily tell the difference between an 85" viewed from 6' and a 170" viewed from 12 ', the viewing angle is the same but the viewing experience is not. The same goes for sound, near field listening at 6' is different to 12'.
I would sit 12 from a 170" screen but not 6' from a 85", others may feel differentially, thats their choice.

And if all you had was an 85" - how far would you sit from it?
Quote:
No you are definitely not looking at them properly. Zooming to 300% is liking looking at you projector screen though a set of binoculars, its silly.
Follow the instruction I gave. Display the images 1:1 (download them and load in photo editor to be sure you have 1:1). Then measure the height of the small image on screen and view the image from 10 times that distance to see what a 8k and 4k image looks like when viewed at 1 times picture height or about 84 degrees viewing angle, closer then just about anyone would ever want to sit.. Remember the full image is 10 times larger and wont fit on just about any PC monitor so a crop is used.
The larger image must be viewed from 5 times its height because it is twice as large. If it wont fit at 1:1 (100%) on the monitor at cant really be used.
Double the above distances if you want to see what 2 times image height looks like (about 42 degrees viewing angle), most people find even that too much for comfort. Its like viewing an 85" screen from 8'.
Anyone who can tell 8k from 4k at 2x picture height (42 degrees) deserves to win a prize.

I don't see how looking at images on a 20" PC monitor set to 1280x1024 is going to accomplish anything.
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post #205 of 676 Old 09-22-2012, 09:06 AM
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Quote:
Originally Posted by mcnabney View Post

Resolution x number of color channels x frames per second x color bit depth = number of bits per second of raw uncompressed video
So a ten bit 8K120 would be (7,680×4,320) x 3 x 120 x 10 = 119,439,360,000 bits per second or about 120Gbs.
The original goal for Super Hi-Vision was that it would have an uncompressed bitrate of 72 Gbps (8K at 60 fps with 12-bit RGB) as seen in this 2010 NHK article but due to technical limits the NHK uses 24 Gbps (my guess is that they use 8-bit 4:2:0 YCbCr). Also the current goal for Super Hi-Vision increased due to the decision to use 120 fps and as seen in this more recent NHK article the uncompressed bitrate is now 144 Gbps (8K at 120 fps with 12-bit RGB).

Quote:
Originally Posted by Joe Bloggs View Post

For the SHV Olympics demos (that were done in the UK - using NHK's cameras), they used 60 fps.
http://www.engadget.com/2012/07/31/super-hi-vision-eyes-on
Agreed, and I have read several articles that said it was at 60 fps. My guess is that the NHK used 8-bit 4:2:0 YCbCr since that would give an uncompressed bitrate of 23.8 Gbps.

Quote:
Originally Posted by Lee Stewart View Post

Sharp showed an 85" SHV display. That is one inch larger than the LG/Sony 4K TVs that will go on sale this year.
A person with 20/20 vision only starts to see the benefit of 8K resolution on a 84" display at a distance of about 6 feet. As such there is a large display size range where a 4K resolution will make more sense for the average person. For example in a BBC London survey the average TV viewing distance was 2.7 meters. At some point in the future I think that 8K UHDTV will make sense as a consumer TV standard but I do wonder whether it will happen in the next 20 years.

Quote:
Originally Posted by Owen View Post

30 degrees is normally considered the correct distance for 1080 (2k) therefore 4k=60 degrees and 8k= 120 degrees. Whoever made that diagram you posted cant add up, double 30 is not 55.
The NHK is simply taking into account that for large displays at close distances the center of the display is closer to where you are than the sides of the display.
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post #206 of 676 Old 09-22-2012, 10:12 AM
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Quote:
Originally Posted by Lee Stewart View Post

Sorry - the diagram is correct, it is you that is wrong. Right from JBC:

Fair enough, I did not factor in the super close viewing distance and its affect on distance to screen edges.
It goes to shows that a small difference in viewing distance is critical at such high resolutions. At greater distances that's much less relevant and I seriously doubt many people will be prepared to sit at 0.75 x image height. I like a big image and wide viewing angle but that's insane.
When we have to worry about not being able to resolve detail either side of the screen because its further away then the center we have lost the plot IMHO. Sit a bit further back and we cant resolve any of the screen which is what I have been pointing out.
Quote:
Originally Posted by Lee Stewart View Post

Did you see any of the 2012 Olympics demos of 8K in London or Wash. DC?

No, is it better than a still image form a top grade DSLR?
Quote:
Originally Posted by Lee Stewart View Post

And if all you had was an 85" - how far would you sit from it?
Certainly not the 3' recommended by NHK.
Quote:
Originally Posted by Lee Stewart View Post

I don't see how looking at images on a 20" PC monitor set to 1280x1024 is going to accomplish anything.


The size and resolution of the monitor is irrelevant, its all about pixels per degree of vision.
If you cant even be bothered to look at the images in the way I requested why comment?
Hopefully others will take more of an interest, they might learn something.
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post #207 of 676 Old 09-22-2012, 10:31 AM
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Originally Posted by Randomoneh View Post

[*] Will effective acuity be higher in the future due to very high-contrast displays making today's calculations obsolete? Very likely.

Overall screen contrast will improve but the drop in MTF at high spatial frequencies in the video source will remain unless there is a breakthrough in lens technology.
Existing displays have 100% MTF right out to the pixel level so there is no real limitation in that department for displays already.
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post #208 of 676 Old 09-22-2012, 10:34 AM
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The 85" prototype|proof-of-concept|"roadshow" 8K4K UHDTV from NHK pictured at this 2011 EBU demo (link) looks to be 5 or 6 feet from the front row seats . . . although placement may be dictated partially by the need to allow second row viewers a clear sight line...?!
_
_
Note also the experimental integrated audio system: This set is designed to provide full 22.2 channel surround sound playback in rooms where installing 22 separate satellite speakers is impractical; instead, it uses 100+ "small" speaker units in a frame around all four sides of the display, plus some proprietary active-DSP|soundbar-style technology, to deliver "the same" playback soundfield to the audience. (It's not clear from the article whether or not there there were also separate subs or some speakers placed in the rear corners of the room.)
_

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post #209 of 676 Old 09-22-2012, 01:25 PM
 
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Quote:
Originally Posted by Richard Paul View Post

The original goal for Super Hi-Vision was that it would have an uncompressed bitrate of 72 Gbps (8K at 60 fps with 12-bit RGB) as seen in this 2010 NHK article but due to technical limits the NHK uses 24 Gbps (my guess is that they use 8-bit 4:2:0 YCbCr). Also the current goal for Super Hi-Vision increased due to the decision to use 120 fps and as seen in this more recent NHK article the uncompressed bitrate is now 144 Gbps (8K at 120 fps with 12-bit RGB).
Agreed, and I have read several articles that said it was at 60 fps. My guess is that the NHK used 8-bit 4:2:0 YCbCr since that would give an uncompressed bitrate of 23.8 Gbps.

Hey - didn't you say they weren't going to use 4:2:0 for SHV. That only 4:2:2 or 4:4:4 would be used.
Quote:
A person with 20/20 vision only starts to see the benefit of 8K resolution on a 84" display at a distance of about 6 feet. As such there is a large display size range where a 4K resolution will make more sense for the average person. For example in a BBC London survey the average TV viewing distance was 2.7 meters. At some point in the future I think that 8K UHDTV will make sense as a consumer TV standard but I do wonder whether it will happen in the next 20 years.
The NHK is simply taking into account that for large displays at close distances the center of the display is closer to where you are than the sides of the display.

I don't understand why you are showing a recommended seating chart that stops at 2160 when you talking about 8K/4320. The recommended viewing distance from NHK on an 8K 84" TV is .75 picture height. PH = 44" x .75 = 33" - just under 3 feet - not the 6 feet that you claim.

SHVVA_zps5132ca47.jpg
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post #210 of 676 Old 09-22-2012, 01:38 PM
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Quote:
Originally Posted by Owen View Post

Overall screen contrast will improve but the drop in MTF at high spatial frequencies in the video source will remain unless there is a breakthrough in lens technology.
Existing displays have 100% MTF right out to the pixel level so there is no real limitation in that department for displays already.
Do you know how minimum perceptible / separable acuity works? If brightness of a point / line is high enough (assuming contrast is high enough) - size / spacing doesn't matter.
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