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True 4K / Native 4K - Pixel Shift - Help me understand it all?

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57 minutes ago, :) al said:

it is true. from the horse. they survey all

 

https://ispspeedindex.netflix.com/country/australia/

 

Screen Shot 2017-10-15 at 2.54.33 pm.png

 

and this is how we rate as a country our wonderfull high of 3,61 average of 3.49 and low of 3.38

 

Screen Shot 2017-10-15 at 2.55.51 pm.png

Al that graph has absolutely zero to do with the actual available content on Netflix. That's surveying the average throughput on netflix through entire ISPs this is 480p/720p etc right up to UHD, and its average throughput, so people on their crappy tablets, everything. Since a small portion of Australia have internet connections fast enough and a Netflix 4k app to even show you the 4k content, I hardly think this is telling us anything at all.

 

That would be like surveying the average router activity across all internet connections in Australia, then averaging them and claiming that's how fast our internet is, when some people such as myself on full fiber to the home NBN can and do get 100Mbit throughput all day long.

 

If that's the angle you are coming from, fine, but that's got diddly squat to do with what actual content exists on netflix.

 

Netflix even say so themselves:

 

The Netflix ISP Speed Index lists the average prime time bitrate for Netflix content streamed to Netflix members during a particular month. For ‘Prime Time’, we calculate the average bitrate of Netflix content in megabits per second (Mbps) streamed by Netflix members per ISP. We measure the speed via all available end user devices. For a small number of devices, we cannot calculate the exact bitrates and streaming via cellular networks is exempted from our measurements. The speed indicated in the Netflix ISP Speed Index is not a measure of the maximum throughput or the maximum capacity of an ISP. 

 

Also, Al, did you look up the US? UK? Its hardly any different.

 

https://ispspeedindex.netflix.com/country/us/

 

UK

 

https://ispspeedindex.netflix.com/country/uk/

 

Pretty flawed analytical system if you ask me.

 

 

Edited by Javs

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10 minutes ago, Javs said:

Al that graph has absolutely zero to do with the actual available content on Netflix. That's surveying the average throughput on netflix through entire ISPs this is 480p/720p etc right up to UHD, and its average throughput, so people on their crappy tablets, everything. Since a small portion of Australia have internet connections fast enough and a Netflix 4k app to even show you the 4k content, I hardly think this is telling us anything at all.

 

That would be like surveying the average router activity across all internet connections in Australia, then averaging them and claiming that's how fast our internet is, when some people such as myself on full fiber to the home NBN can and do get 100Mbit throughput all day long.

 

If that's the angle you are coming from, fine, but that's got diddly squat to do with what actual content exists on netflix.

 

Netflix even say so themselves:

 

The Netflix ISP Speed Index lists the average prime time bitrate for Netflix content streamed to Netflix members during a particular month. For ‘Prime Time’, we calculate the average bitrate of Netflix content in megabits per second (Mbps) streamed by Netflix members per ISP. We measure the speed via all available end user devices. For a small number of devices, we cannot calculate the exact bitrates and streaming via cellular networks is exempted from our measurements. The speed indicated in the Netflix ISP Speed Index is not a measure of the maximum throughput or the maximum capacity of an ISP. 

 

Also, Al, did you look up the US? UK? Its hardly any different.

 

https://ispspeedindex.netflix.com/country/us/

 

UK

 

https://ispspeedindex.netflix.com/country/uk/

 

Pretty flawed analytical system if you ask me.

 

 

maximum throughput of ISPs is worth cobblers though

 

the above reality is more what i and others i interact with experience. basically come peak viewing times and it all goes to sh!t. 

 

its actually pretty real as it gets past the BS that the isps try to pass off as speeds capable. capable when ? its why the ACCC is all over them now jumping on their tails. hopefully in time when they claim a certain rate it will be at peak times when people are all watching. 

 

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3 minutes ago, :) al said:

the above reality is more what i and others i interact with experience. basically come peak viewing times and it all goes to sh!t. 

Well it's certainly not my reality, Al. It misrepresents what those fortunate enough to have better internet connections routinely obtain from Australian Netflix. 

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8 minutes ago, :) al said:

maximum throughput of ISPs is worth cobblers though

 

the above reality is more what i and others i interact with experience. basically come peak viewing times and it all goes to sh!t. 

 

its actually pretty real as it gets past the BS that the isps try to pass off as speeds capable. capable when ? its why the ACCC is all over them now jumping on their tails. hopefully in time when they claim a certain rate it will be at peak times when people are all watching. 

 

You might be misinterpreting the data, Its the average throughput at a certain time of the streaming bit-rate of all users, not how slow the connection is.

 

Netflix claim you only need around 5mbit to watch 1080p streams, and lets face it, most people are not watching 1080p streams, most are probably 720p at best if you look at the really big picture here, so many of the people are going to be teenagers on laptops sitting on their bed looking at Netflix in a browser window, hell there are heaps of shows on netflix which are not even full HD let alone UHD.

 

If most people are watching 720p streams (Which I bet you is the reality) then why would the average bitrate climb? I dont get how its relevant though, you are using it as a reason for drop outs and overall bad quality when that is not what they are measuring?

 

My previous house and this house both have 100mbit connections, I pretty much never have a stream stuff up mid way, but I have had many discs skip and stop! Its pretty ironic actually. My copy of Lucy on UHD is not well at all, it does not like being played.

 

None of this changes the fact that a UHD stream on Netflix uses 7GB per hour of content, that's not a shabby data rate for a streaming service. I think its very respectable.

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26 minutes ago, Javs said:

 

If most people are watching 720p streams (Which I bet you is the reality) then why would the average bitrate climb? I dont get how its relevant though, you are using it as a reason for drop outs and overall bad quality when that is not what they are measuring?

That is reality for me and many people. You might be lucky with 100mbit but I can tell that is a very small proportion of people out there

 

in anycase my point was for best experience I'd rather watch on disc. Which is what you said to. So I don't get what's to argue ?

 

as i mentioned we spend so much of gear with capability I see no point in pissing things away at source. Am not really sure who that's kidding. Sure not doing anything for me,

 

We watch stuff on Netflix for sure even movies but where disc experience is available for the full fat version audio or video I'll take that any day of the week.

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9 minutes ago, :) al said:

That is reality for me and many people. You might be lucky with 100mbit but I can tell that is a very small proportion of people out there

 

in anycase my point was for best experience I'd rather watch on disc. Which is what you said to. So I don't get what's to argue ?

 

as i mentioned we spend so much of gear with capability I see no point in pissing things away at source. Am not really sure who that's kidding. Sure not doing anything for me,

 

We watch stuff on Netflix for sure even movies but where disc experience is available for the full fat version audio or video I'll take that any day of the week.

There really is no argument here Al,

 

You were saying Netflix essentially has nothing over 3mbit worth of content, I say that couldn't be further from the truth is all... Since this seemed to stem from the discussion of discernible difference between UHD Netflix content and 1080p Bluray.

 

If you want to talk about ISP's that's an entirely different discussion dont you think? Whats it got to do with video quality I am seeing while watching 4k Netflix?

 

I guess i mistook your original point? Which is you dont have fast enough internet to stream Netflix properly? If so, then yeah mate by all means go 100% disc. Its never going to become my primary critical viewing platform either, but then again I dont even have the ability to watch free to air TV since I hate it, so, for any shows I want to watch, its either download, or Netflix. Films are not the only things available for viewing.

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4 hours ago, Javs said:

I get what you are saying nd I agree with you mostly, but you seem to be fixating on the idea of us thinking we like 4k because it offers 4k of visible resolution, you are demonstrating in your posts, and the white paper does also, that if you had video encoded at 4k, you have far higher MTF values for the content up to about 3k,

That's right, no such thing as 4K video with 4K actual usable resolution even in lab perfect capture conditions.

The purpose of my posts was to explain to the pixel obsess out there why a "true" 4K display is not needed, I am NOT saying 4K video is without benefit so can we drop that please.

 

4 hours ago, Javs said:

what about the films shot in 6.5 and 8k??? There are lots of them now. Are we ignoring those too? Those will have much greater MTF too.

The video still has to be low pass filtered to fit within the sampling limit of a 4K system so MTF is still going to be in the 25-30% range at 3K and effectively zero at 4K. Nyquist has us by the nuts.

There are small MTF gains to be had by capturing in 6K, 8K or even higher and then down scaling but they are very subtle. Panavision worked out that 3 times over sampling was ideal.

5 hours ago, Javs said:

There is a very real difference between a 2k film from 4k master and a 4k film from a 4k master,

Don't fall into the trap of comparing totally different masters mate, its an apples to oranges comparison, they where mastered to look different. Down scaling the 4K version to 2K to strip out any resolution over 2K and then scale back up to 4K for comparison is a much fairer as it removes all the other mastering variables like colour gamma, data rate compression etc. When you do that its remarkable how difficult if not impossible it is to pick them apart in a double blind test where you dont know which you are viewing, and thats with the best quality digitally shot content. Sure if you blow the images up and study them closely you can tell which is which but we dont view movies like that.

This ties in with what was explained in the Panavision video, its low to medium frequency MTF thats important for movie viewing not super high "resolution".

 

I find it remarkable just how effective and impressive 1080 Bluray can be, the highest quality titles look fantastic and I'm completely satisfied with the picture quality. When we consider that 1080 Bluray is only delivering about 1.5K luma and about 0.75K chroma resolution its all the more remarkable. Even then few 1080 Bluray tiles are up to the standard set by the very best titles which proves that the quality of the original video source, the subsequent mastering and encoding dominate what we see in most cases. The 1080 Bluray format is extremely capable when the rest of the chain is up to scratch.

 

5 hours ago, Javs said:

So, you are saying because films move they are useless at higher resolution, what about when they DONT move? Like, in at least 30-40% of films, there are countless shots that are totally still and only an object moves through the frame, sorry but that is a pretty lame point of view, its totally flawed.

Not as flawed as you suggest. It almost imposable to hold a camera completely still, even on a very good tripod. Just a small vibration is enough to move the image as seen by the camera a single pixel or more during the shutter open period and resolution is insensately halved or worse. We dont notice because there is still plenty of resolution to get the job done and there is an averaging effect over consecutive frames.

To reliably capture high resolution images we need a fast shutter speed, the faster the better to mitigate the effects of vibration during the shutter open period. The 1/24th second shutter speed used for motion picture capture is totally unsuitable for high resolution capture and there is normally a camera operator holding onto the camera, in many cases supporting the camera.

Any lens zoom magnifies movement.

 

Limitations also apply to focus, unless its a long distance shot with the lens focused to infinity the camera is focused manually via a distance measurement from subject to lens which is prone to error. With the large lens aperture openings used in most shots to provide strong depth of field which puts the subject in focus and the background out of focus even a 1cm error in subject distance will throw focus off and trash resolution.

 

6 hours ago, Javs said:

Again, I am not sure why you are shooting the format down??? Were you the guy saying the same thing when DVD was around and bluray was just around the corner?

I know it comes across that way mate, but its not my intention to shoot the format down. I just want to cut through the 4K marketing BS and the misunderstandings it has generated in the minds of the consumers.

 

4K Bluray has thus far done a very good job of shooting itself down as far as I am concerned by the movies that are chosen for release. Out of the movies I have viewed since the release of 4k Bluray over 90% are not available on 4K disk and the titles that are where movies I do not think highly off or are old and no longer of interest. The Revenant is top of my dislike list, couldn't even watch it to the end.

 

I always thought DVD was crap, much better than VHS tape but I was never satisfied. I started upscaling DVD up to 300% with sharpening on a PC back in 2002-2003 in an attempt to get a better result. It was an improvement but still lipstick on a pig.

 

7 hours ago, Javs said:

There is no scenario in which extra resolution and its accosiated benefits are going to make a film look worse. You may hit a platau with some movies, but its never going to make them look worse.

True, but for the majority of movies, especially older titles shot on film, its obvious they are not even using the full capabilities of 1080 Bluray for whatever reason. Unless the mastering or compression was the culprit I fail to see how more pixels are going make much of a difference.

 

7 hours ago, Javs said:

Well the 'rips' are the real deal, they are proper remux from the original discs now, so, perhaps you havent looked around recently.

Well maybe things have changed recently, but the titles I have looked at have been around for a few months and they where no better than the 1080 Bluray. Yet people raved about how great 4K is when viewing these titles that are 4K in pixel count only.

Those people obviously believe what they want to believe.

 

7 hours ago, Javs said:

As for MTF corrected screen? Please elaborate on this, explain what you are doing here?

MTF correction is sharpening, they are one and the same. I run the video though FFDShow first for upscaling with luma and chroma sharpening which provides a subtle low to mid frequency boost with little effect at the top end . I then run it through MadVR for a final touch up depending on the title. For lower quality titles I typically turn MadVR off and run just FFDShow.

I dont like the way MadVR looks on its own and I will not use it that way.

 

 

 

 

 

 

 

 

 

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28 minutes ago, Javs said:

You were saying Netflix essentially has nothing over 3mbit worth of content, I say that couldn't be further from the truth is all... Since this seemed to stem from the discussion of discernible difference between UHD Netflix content and 1080p Bluray.

Absolutely not what am saying. What am saying is 3mbps is about best most people going to experience at peak. Which isn't good enough quite frankly. 

 

even if I had 7mbps or 100mbps I would still reach for the disc because I rather as mentioned have the full fat :)

 

i ser no sense. On other hand by  all means the will be stuff I will watch eg doco cooking show etc just as you would but for very best experience it is still disc for me and unlikely to change because even with its throttling to match capabilities Netflix still have to cater for lowest common denominator and why we don't get full uhd rips streaming over the net from any of these servers. The only one we had was kaleidoscape but even that was download and view not stream :)

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1 hour ago, Owen said:

That's right, no such thing as 4K video with 4K actual usable resolution even in lab perfect capture conditions.

The purpose of my posts was to explain to the pixel obsess out there why a "true" 4K display is not needed, I am NOT saying 4K video is without benefit so can we drop that please.

 

The video still has to be low pass filtered to fit within the sampling limit of a 4K system so MTF is still going to be in the 25-30% range at 3K and effectively zero at 4K. Nyquist has us by the nuts.

There are small MTF gains to be had by capturing in 6K, 8K or even higher and then down scaling but they are very subtle. Panavision worked out that 3 times over sampling was ideal.

Don't fall into the trap of comparing totally different masters mate, its an apples to oranges comparison, they where mastered to look different. Down scaling the 4K version to 2K to strip out any resolution over 2K and then scale back up to 4K for comparison is a much fairer as it removes all the other mastering variables like colour gamma, data rate compression etc. When you do that its remarkable how difficult if not impossible it is to pick them apart in a double blind test where you dont know which you are viewing, and thats with the best quality digitally shot content. Sure if you blow the images up and study them closely you can tell which is which but we dont view movies like that.

This ties in with what was explained in the Panavision video, its low to medium frequency MTF thats important for movie viewing not super high "resolution".

 

I find it remarkable just how effective and impressive 1080 Bluray can be, the highest quality titles look fantastic and I'm completely satisfied with the picture quality. When we consider that 1080 Bluray is only delivering about 1.5K luma and about 0.75K chroma resolution its all the more remarkable. Even then few 1080 Bluray tiles are up to the standard set by the very best titles which proves that the quality of the original video source, the subsequent mastering and encoding dominate what we see in most cases. The 1080 Bluray format is extremely capable when the rest of the chain is up to scratch.

 

Not as flawed as you suggest. It almost imposable to hold a camera completely still, even on a very good tripod. Just a small vibration is enough to move the image as seen by the camera a single pixel or more during the shutter open period and resolution is insensately halved or worse. We dont notice because there is still plenty of resolution to get the job done and there is an averaging effect over consecutive frames.

To reliably capture high resolution images we need a fast shutter speed, the faster the better to mitigate the effects of vibration during the shutter open period. The 1/24th second shutter speed used for motion picture capture is totally unsuitable for high resolution capture and there is normally a camera operator holding onto the camera, in many cases supporting the camera.

Any lens zoom magnifies movement.

 

Limitations also apply to focus, unless its a long distance shot with the lens focused to infinity the camera is focused manually via a distance measurement from subject to lens which is prone to error. With the large lens aperture openings used in most shots to provide strong depth of field which puts the subject in focus and the background out of focus even a 1cm error in subject distance will throw focus off and trash resolution.

 

I know it comes across that way mate, but its not my intention to shoot the format down. I just want to cut through the 4K marketing BS and the misunderstandings it has generated in the minds of the consumers.

 

4K Bluray has thus far done a very good job of shooting itself down as far as I am concerned by the movies that are chosen for release. Out of the movies I have viewed since the release of 4k Bluray over 90% are not available on 4K disk and the titles that are where movies I do not think highly off or are old and no longer of interest. The Revenant is top of my dislike list, couldn't even watch it to the end.

 

I always thought DVD was crap, much better than VHS tape but I was never satisfied. I started upscaling DVD up to 300% with sharpening on a PC back in 2002-2003 in an attempt to get a better result. It was an improvement but still lipstick on a pig.

 

True, but for the majority of movies, especially older titles shot on film, its obvious they are not even using the full capabilities of 1080 Bluray for whatever reason. Unless the mastering or compression was the culprit I fail to see how more pixels are going make much of a difference.

 

Well maybe things have changed recently, but the titles I have looked at have been around for a few months and they where no better than the 1080 Bluray. Yet people raved about how great 4K is when viewing these titles that are 4K in pixel count only.

Those people obviously believe what they want to believe.

 

MTF correction is sharpening, they are one and the same. I run the video though FFDShow first for upscaling with luma and chroma sharpening which provides a subtle low to mid frequency boost with little effect at the top end . I then run it through MadVR for a final touch up depending on the title. For lower quality titles I typically turn MadVR off and run just FFDShow.

I dont like the way MadVR looks on its own and I will not use it that way.

Thats a good post, thanks. I think we are mostly on the same page here.

 

In that case I am doing 'MTF Correction' also, but using MadVR NGU scaling.

 

Its really quite excellent.

 

This might interest you, I did this a while back investigating MadVR, its the same image I posted before, and it fits into what we are discussing.

 

So I took the control 5.7k  holiday image and shrunk it down to 2160p, then I output a specific 1080p version of the same file using the same 'master' as the source.

 

Then what I did is compared them all using MadVR and essentially vanilla up-scaling from Kodi, which I think is nearest neighbour or something fairly default, then I also up-scaled using the MadVR NGU settings I use for 99% of my viewing and compared them all against the original master image. Doing this of course we know what the original would look like in true 4k as it were, and we can see how good/close up-scaling can get to that original.

 

Control UHD Master vs 1080p Vanilla Up-scale

 

http://screenshotcomparison.com/comparison/113576

 

1080p Vanilla Up-scale vs MadVR NGU Up-scale

 

http://screenshotcomparison.com/comparison/113575

 

MadVR NGU Up-scale vs Control UHD Master

 

http://screenshotcomparison.com/comparison/113573

 

Indeed NGU comes very close to the original, but not quite there yet. I should note the Control UHD is still passing through MadVR, but all its doing is Chroma up-sampling, no sharpening.

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i think personally as i posted in one of the opening posts that to keep in mind with uhd for first time we are likely even seeing 2K

 

for the same reasons we wont see 4K off 4k discs we also wouldn't have seen 2K off our previous 2k formats. so hence there is certainly something to be gained with the 4k uhd format even if it is giving us 2K for first time. discs like wonder woman are great example of this. its a 2K DI and yet looks stunning ! and there are as javs has pointed out plenty of discs with 6k and such source. so we will be getting beyond 2k with uhd. i too believe its likely pegged around 3k maybe 3.5k at best but this is a step forward from blu-ray.

 

there are also posts from likes of chris deering explaining the gains WCG bringing. i wish can find. similarly with high dynamic range working in with it its a great end result. not only for new releases like wonderwoman but also back catalog in ET, first encounter 3rd kind and original blade runner and the like which with their remasters are trully experiencing now in the best we ever have. i received about 6 discs in the last week and with 139 released in just over a year and more to come I would be very suprised if there wasnt something for everyone there.

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21 hours ago, Owen said:

I dont like the way MadVR looks on its own and I will not use it that way.

Hi Owen, have you tried the new NGU algorithms for upscaling with MadVR?

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Question for the experts.

 

Using a JVC X30, that i have no reason to upgrade, would there be much advantage in feeding it a 4K source over the same 1080p source. Just say for comparisons sake, at 1080p movie at 25Mbps against the same film in 4k at 50+Mbps. Obviously the projector will downscale but was thinking that the extra bitrate would help?

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1 minute ago, SLE355 said:

Question for the experts.

 

Using a JVC X30, that i have no reason to upgrade, would there be much advantage in feeding it a 4K source over the same 1080p source. Just say for comparisons sake, at 1080p movie at 25Mbps against the same film in 4k at 50+Mbps. Obviously the projector will downscale but was thinking that the extra bitrate would help?

I went x7000 and its new light engine with better grid polarisers for better contrast etc  could be attributable to a few things but. i found the upgrade x35 to x7000 VERY worthwhile and thats even with the x35 doing very good things in 1080p 

 

as i mentioned its good chance for first time we are actually seeing 2k at the very least. for others its 3-3.5k at best ! then there are other aspects UHD such as HDR and WCG. all to good benefit. and i say this now enjoying for quite some time a couple of years this series of jvc.

 

@Kazz went x35 to x5000 as well so maybe worth checking in what thoughts were in the move :)

 

 

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13 hours ago, :) al said:

As I mentioned its good chance for first time we are actually seeing 2k at the very least. for others its 3-3.5k at best ! then there are other aspects UHD such as HDR and WCG. all to good benefit. and i say this now enjoying for quite some time a couple of years this series of jvc.

That may be true, but when you talk about it like that its confusing for people, since you need the 4k resolution in order for the lowpass to roll off, otherwise if you stopped the MTF at 2k without a roll-off you will have pretty extreme moire.

 

So, it really is 4K. You need to be including the whole low pass rolloff when we talk about resolutions as that's the 'bigger picture'. 4K is, after all, the sum of its parts,

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14 hours ago, :) al said:

I went x7000 and its new light engine with better grid polarisers for better contrast etc  could be attributable to a few things but. i found the upgrade x35 to x7000 VERY worthwhile and thats even with the x35 doing very good things in 1080p 

 

as i mentioned its good chance for first time we are actually seeing 2k at the very least. for others its 3-3.5k at best ! then there are other aspects UHD such as HDR and WCG. all to good benefit. and i say this now enjoying for quite some time a couple of years this series of jvc.

 

@Kazz went x35 to x5000 as well so maybe worth checking in what thoughts were in the move :)

 

 

 

I'm glad I went from the X35 to the X5000, was definitely a worthwhile upgrade, don't get me wrong the X35 was a great PJ but the X5000 is definitely a step up in PQ, the biggest difference is light output as the X5000 can get much brighter.  Also the ability to watch 4K UHD with HDR that the X35 doesn't have.

 

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On the true 4K / Pixel shift, what is it like using one of the pixel shift projectors at a 4K nice large computer screen/projector? Anyone have any experience on it? I take it due to lamp lifespan, it really isn't a recommended use?

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