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Mtf Of Blu-ray/hd-dvds


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Why is my evidence irrelevant? I have shown that negatives from a Cinema film camera are not capable of providing 1920 lines per picture width and 1080 lines per picture height at anywhere near 100% MTF. (by the way, I was not aware that film was no longer in use for movie production :D).

As for digital camera’s like Panavisions Genesis, it captures at 5760x3240 or 3 times 1920x1080 then down scales in the camera to 1920x1080 for output to a standard 1080 Sony video recorder (VTR), just like any Sony 1080 HD camera. The quality is much higher then a native 1920x1080 camera BUT, it’s still not going to provide 100% MTF at 1920x1080, lucky if it manages 50% MTF.

http://www.panavision.com.au/PDFs/Info-PV/Genesis_FAQs.pdf

http://www.panavision.com.au/PDFs/Manuals-...UsersManual.pdf

The Genesis is not a revolutionary device that defies the resolution and MTF laws that bind other digital cameras. It has a 12MP sensor with appropriate anti alias filters and uses normal Panavision lenses which are not perfect. The lens and camera both have a characteristic MTF curve and those curves combine to give the overall response at output.

Digital sharpening can be used to push up the MTF curve, but only by a limited amount or aliasing and artifacts will be noticeable. 100% MTF at the resolution limit is just not possible, and that is what I have been saying all along.

yeah right owen, the genises is no different to a hd tv camera ?huh?, if it makes you sleep any better... this post of your is pretty typical really of all your posts dismissing with absolutely no evidence to backup apart from your own theories & subjective opinion on things..

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yeah right owen, the genises is no different to a hd tv camera ?huh?, if it makes you sleep any better... this post of your is pretty typical really of all your posts dismissing with absolutely no evidence to backup apart from your own theories & subjective opinion on things..

That's not what Owen said:

it captures at 5760x3240 or 3 times 1920x1080 then down scales in the camera to 1920x1080 for output to a standard 1080 Sony video recorder (VTR), just like any Sony 1080 HD camera. The quality is much higher then a native 1920x1080 camera BUT, it’s still not going to provide 100% MTF at 1920x1080, lucky if it manages 50% MTF.

He acknowledged the quality of the Genesis output should be higher than a normal HD camera, but stated that the output resolution is the same, which is not in dispute.

The language being used in some of the posts here is getting rather emotive...

Cheers,

BAC

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yeah right owen, the genises is no different to a hd tv camera ?huh?, if it makes you sleep any better... this post of your is pretty typical really of all your posts dismissing with absolutely no evidence to backup apart from your own theories & subjective opinion on things..

I think what owen meant was that the genesis is no different from any camera that exists in this universe - It has to obey the laws of physics. It is subject to the same physical constraints and requirements. Even the best camera in the world operating at the absolute upper end of expectations still has to conform to the same laws that govern all matter and forces in the universe.

You can't simply dismiss Nyquist limit as theory - this is a fundamental property of information theory and is as much a "law" as gravity.

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We have not seen one shred of evidence from you that film & film cameras do not have the capability to provide more than 1920x1080, all we have seen is some "fabricated" theory of yours which is utter non-nonsense and as bad as your cock-eyed theory trying to explain the abilities of movie cameras based on digital still slrs even mlx thought was a bit fanciefull and wouldnt float at the smpte !

Now if your theory is fact, which it isnt, its fabricated by you, there would surely be some evidence out htere to support. We have not seen any from you. please provide it.

On the contrary I have provided more than plenty info saying otherwise of the resolution capability of film and film cameras and lenses. additionally hosko who studied film and knows what he is talking about, challenged you on the validity and we are yet to see any evidence from you to back up your fanciful theories.

I have provided plenty of evidence, but you I either did not read it or choose to ignore it.

My “theory” as you call it is based on all available evidence I can find, none of it is in contradiction.

At no stage have I said that film is limited to 1902x1080 resolution. What I have consistently stated is that cinema film is not capable of providing 100% MTF at 1920 lines per picture width by 1080 lines per picture height, and I supplied multiple links to support that claim.

Please provide a link to just one film or digital camera that can provide 100% MTF at 1920 lines per picture width by 1080 lines per picture height. I have not been able to find any camera with such performance.

The “Lowry Process” scans at 4000 pixel across the frame or double 1920.

The Nyquist limit is 2000 pixels and the typical MTF at the Nyquist limit is 20%.

Since the MTF of the system is the sum of MTF losses in the lens, film and scanner the MTF at 1920 will be much less then 20%.

The Genesis should be better then that, as it captures at 3 times 1920, so MTF at 1920 will be higher, but NEVER 100%.

you have not provided one set of evidence to indicate the ability of 4k scanning by the lowry process provides an inability of lack of resolution for 1920x1080 for the hi-def disc formats, infact quite to the contrary I have provided much independant information saying otherwise. please provide some independant evidence to dispute, and please no fabricated BS or fanciful theories of yours.

I have not said that there is film has a “lack of resolution for 1920x1080” you are the one that has attributed that to me. I have consistently stated over and over and over that film does not provide 100% MTF at 1920 lines per picture width by 1080 lines per picture height, and I have provided ample evidence to support that claim.

you have not provided any evidence to suggest the genesis camera or any of hte multitude of cameras which I provided links to info on cannot capture adequate resolution for 1920x1080 required for hd dvd and blu-ray, on the contrary I provided information showing these cameras can output 2k -4k resolution which is twice to four times that required for hd dvd and blu -ray and more than sufficient for those purposes. we have not see nany evidence from you to dispute apart from your pathetic comparison with digital still cameras which has no relevance to this discussion.

Actually the Genesis down scales in the camera and only outputs 1920x1080, NOT 4k.

The Canon SLR I linked is exceptional, it is very close to the theoretical limits of a camera with a 16MP sensor (compared to the 12MP sensor in the Genesis) , and with digital sharpening even exceeds those limits at the expense of a little aliasing. Even then it is not capable of providing 100% MTF at 1920 lines per picture width by 1080 lines per picture height.

To exceed the performance of the Canon the genesis would need to defy the limitations of lenses and digital image capture. To get 100% MTF at 1920x1080 it would have to defy those real world limits by a HUGE margin.

Please provide a link to ANY camera that can do that, I cant find one anywhere.

interesting so even 1920 x 1080 or a 70" still isnt adequate for even your current scenario. but what I find more disturbing though is that for how long now you have been castigating people in regards display size and how they should sit a certain distance from it all as per the visual aquity chart. there are literally countless posts from you on this forum, infact yoru known for being obsessed about it, yet you now say that the chart is irelevant since you can never resolve the resolution you are tryign to resolve. how do you exactly sleep at night ? putting forward information to people under such a false pretense.

I never said the viewing distance calculators are irrelevant, you did. In fact I consider them conservative.

The best 1080 video does have some useful information out towards the pixel resolution limit, but that detail is so low in contrast that you need to be at least as close to the screen as viewing distance calculations recommend to see it.

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I think the issue here is some are arguing purely from a capture point at the time of photograpy, while other are arguing of what actually makes it to the end product - HD DVD/Blu-ray.

Actually I never made that distinction. Cinema film cant provide 100% MTF at 1920 lines per picture width by 1080 lines per picture height, neither can a digital camera. So how are we magically going to get 100% MTF at 1920x1080 on a HD disk with video compression?

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Let me see if I can pause for breath here. I'll use my checkerboard analogy again.

Let's take our 1920x1080 black and white checkboard again, computer generated, so on the monitor it is pixel perfect. Now let's film that screen with the genesis camera, let it do its stuff, and then view the output. I think - and I could be wrong in this mind you - that what Al is stating is that the output would be a pixel perfect 1920x1080 checkerboard because the Genesis has sufficient resolution to fully resolve and produce a final image of 1920x1080.

What Own et al are saying - and again I could be going wide down leg side on this - is that that final image, while it may well be 1920x1080, will not be a perfect reproduction of our original screenshot, that the black pixels will be dark greyish and the white pixels will be light greyish.

Is that a succinct summation of the two positions? Or should I shut up and go back to hiding in my box? :P

By George I think he’s got it, good man. :D

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Actually I never made that distinction. Cinema film cant provide 100% MTF at 1920 lines per picture width by 1080 lines per picture height, neither can a digital camera. So how are we magically going to get 100% MTF at 1920x1080 on a HD disk with video compression?

because, and boy is this getting tiresome, the source is not, repeat not 1920x1080. It is much higher. 1920x1080 is the end result of transfering the film to the home formats HD DVD and Blu-ray. Do you think what you see in the cinema is 1920x1080? By the time it reaches these formats these limitations and errors have been filtered out, corrected, or, in the case of high effects ladden films been replaced.

And that doesn't even factor in CGI films which are completely and utterly uneffected by MTF.

Put simply it is possible for a Blu-ray aor HD DVD to have 100% resolveable 1920x1080.

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because, and boy is this getting tiresome, the source is not, repeat not 1920x1080. It is much higher. 1920x1080 is the end result of transfering the film to the home formats HD DVD and Blu-ray. Do you think what you see in the cinema is 1920x1080? By the time it reaches these formats these limitations and errors have been filtered out, corrected, or, in the case of high effects ladden films been replaced.

And that doesn't even factor in CGI films which are completely and utterly uneffected by MTF.

Put simply it is possible for a Blu-ray aor HD DVD to have 100% resolveable 1920x1080.

The thing is it does not matter what resolution the film or digital capture is, MTF starts to drop of quite early in the spatial frequency range and continually declines up to the resolution limit, what ever that is.

The resolution limit is where MTF has dropped to the point where no detail is visible; it’s just a grey blur. There is no way to undo MTF loss, other then apply a small amount of sharpening, but you can never come close to recovering 100% MTF at high resolutions with anything shot on a camera, digital or film.

I have always stated that the only way to get 100% MTF is with computer generated images, so unless we only watch CGI content 100% MTF is out of the question.

If CGI is mixed with non CGI source for effects, the CGI content must be blurred or softened to match the MTF curve of the source or the effects will look artificial and out of place.

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The thing is it does not matter what resolution the film or digital capture is, MTF starts to drop of quite early in the spatial frequency range and continually declines up to the resolution limit, what ever that is.

The resolution limit is where MTF has dropped to the point where no detail is visible; it’s just a grey blur. There is no way to undo MTF loss, other then apply a small amount of sharpening, but you can never come close to recovering 100% MTF at high resolutions with anything shot on a camera, digital or film.

I have always stated that the only way to get 100% MTF is with computer generated images, so unless we only watch CGI content 100% MTF is out of the question.

If CGI is mixed with non CGI source for effects, the CGI content must be blurred or softened to match the MTF curve of the source or the effects will look artificial and out of place.

So blu-ray and HD DVD can resolve 100% 1920x1080 for CGI? We are settled on that? Good because my argument was always with the notion that was put forward claiming the formats could not be fully resolved and that they were something of a "scam". So far so good.

Also as to you above comments, yes and no. The point I am trying to make is that you have, for sake of argument, 4 million pixels in the film to digital source. The end result product will only contain 1 million pixels. Even if 50% of the pixels in the original are not good (grey globs) you still have more than enough perfect pixels to harvet for the end print.

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Hi All,

Have been following this "discussion" with great interest and have seen merit in the arguments being raised by both sides. During the course of a little web trawling of my own, I came across this paper which deals with some of the issues being discussed:

Digital Cinema Resolution – Current Situation and Future requirements

Admittedly the data is now 5-6 years old, so it's likely some of the numbers quoted regarding resolution, etc. are out of date, but I think it's still well worth a read as it covers topics like human visual acuity, pixel sampling theory, MTF of 35mm film, etc. (My apologies if the above document has been linked somewhere earlier in this thread, but I didn't notice it)

One other interesting thing I read on the cinematography.com forums is the main limitation with digital technology as of today as far as they are concerned is not the availability of cameras with sufficient resolution, etc., but the lack of suitable portable recording technology to keep pace with the high resolution streams that could be produced.

This is probably the main reason why high end digital cinema cameras like the Genesis resort to "binning" a significant proportion of their sensor resolution and output at "only" 2K (with 2:1 compression applied, BTW).

Cheers,

BAC

a good post there bac, unfortunately as you say the data is quite old now 5-6 years old, and digital camera system have progressed a heap in that time let alone storage systems which quite liekly would have been a limitation back then. Imaging systems though have come a long way since, even with consumer cameras the cmos used in my 40d is a quantam leap up from the 10D from 4-5 years ago, and storage systems we now have means not even dreamed off back then !

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That's not what Owen said:

He acknowledged the quality of the Genesis output should be higher than a normal HD camera, but stated that the output resolution is the same, which is not in dispute.

The language being used in some of the posts here is getting rather emotive...

Cheers,

BAC

sorry but what evidence exactly did owen produce that is evidence that the genesis cant output at 2K or twice that required for 1920x1080 for hd dvd and blu-ray. all we have seen him dismiss is evidence posted on the genesis capabilities and all he has put forward is his own summation and personal subjective view and opinion that I can see.

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I think what owen meant was that the genesis is no different from any camera that exists in this universe - It has to obey the laws of physics. It is subject to the same physical constraints and requirements. Even the best camera in the world operating at the absolute upper end of expectations still has to conform to the same laws that govern all matter and forces in the universe.

You can't simply dismiss Nyquist limit as theory - this is a fundamental property of information theory and is as much a "law" as gravity.

did anyone say the genesis does not obey laws of physics. I think its capabilities were posted. I am yet to see any actual evidence to dispute that.

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Let me see if I can pause for breath here. I'll use my checkerboard analogy again.

Let's take our 1920x1080 black and white checkboard again, computer generated, so on the monitor it is pixel perfect. Now let's film that screen with the genesis camera, let it do its stuff, and then view the output. I think - and I could be wrong in this mind you - that what Al is stating is that the output would be a pixel perfect 1920x1080 checkerboard because the Genesis has sufficient resolution to fully resolve and produce a final image of 1920x1080.

What Own et al are saying - and again I could be going wide down leg side on this - is that that final image, while it may well be 1920x1080, will not be a perfect reproduction of our original screenshot, that the black pixels will be dark greyish and the white pixels will be light greyish.

Is that a succinct summation of the two positions? Or should I shut up and go back to hiding in my box? :P

By George I think he’s got it, good man. :D

Yes Thudd, your example is a good illustration of the principles involved. If an attempt were made to transfer what the Genesis camera recorded onto a high definition disk (BR or HD-DVD) unfortunately there would be an expanse of grey, and possibly the faintest hint of a chequerboard pattern; unless the encoding for the Blu-ray or HD-DVD was set for text mode [not a normal mode, and not used for movies], rather than video mode.

Another, less demanding, example would be a 2-pixel chequerboard pattern. This would result in 960x540 squares. This is at the critical Nyquist limit. The original perfect chequerboard would look like this, as best I can repesent it by typing in characters and formatting the colour:

████████████████

████████████████

████████████████

████████████████

████████████████

████████████████

████████████████

████████████████

How the Blu-ray or HD-DVD authoring codec would encode this 960x540 pattern would be a lower MTF version resembling this:

████████████████

████████████████

████████████████

████████████████

████████████████

████████████████

████████████████

████████████████

Actually it should really even be far lower contrast than that as it is impractical to have even 50% MTF at Nyquist frequency as that would lead to too much visible but aliased (false) detail a little above Nyquist.

If anyone wants to experiment and has the image authoring software, they can create a 2-pixel chequerboard pattern [that is each square in the chequerboard is 2 pixels by 2 pixels] in 1920x1080 format, load it into a video authoring program that duplicates the still as frames in a video and then save the output as a 1920x1080 MPEG video (one of the codecs used for Blu-ray disks). The MPEG encoding parameters should be set to suit video.

They can then play the MPEG on a 1920x1080 digital display and inspect adjacent pixels. They will see light grey and dark grey. They will not see white and black; even very close to the screen. This has to do with sampling theory and the requirement for smooth video, and for avoiding aliasing.

It will no better if a Genesis camera is used instead of a pristine 960x540 square chequerboard created electronically, and it will probably be worse, i.e a lower MTF, but that would depend on the setting used on the camera and the format in which the output was archived prior to creation of the Blu-ray or HD-DVD disk.

Thanks Thudd, for your chequerboard analogy.

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Also as to you above comments, yes and no. The point I am trying to make is that you have, for sake of argument, 4 million pixels in the film to digital source. The end result product will only contain 1 million pixels. Even if 50% of the pixels in the original are not good (grey globs) you still have more than enough perfect pixels to harvet for the end print.

MTF does not discriminate between one pixel and the next ALL pixel data is blurred, the higher the spatial frequency the greater the blur.

100% MTF at a particular spatial frequency infers zero blur and 100% contrast at that frequency, which is not possible for camera’s at high spatial frequencies, 1920x1080 is quite high.

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Yes Thudd, your example is a good illustration of the principles involved. If an attempt were made to transfer what the Genesis camera recorded onto a high definition disk (BR or HD-DVD) unfortunately there would be an expanse of grey, and possibly the faintest hint of a chequerboard pattern; unless the encoding for the Blu-ray or HD-DVD was set for text mode [not a normal mode, and not used for movies], rather than video mode.

Another, less demanding, example would be a 2-pixel chequerboard pattern. This would result in 960x540 squares. This is at the critical Nyquist limit. The original perfect chequerboard would look like this, as best I can repesent it by typing in characters and formatting the colour:

████████████████

████████████████

████████████████

████████████████

████████████████

████████████████

████████████████

████████████████

How the Blu-ray or HD-DVD authoring codec would encode this 960x540 pattern would be a lower MTF version resembling this:

████████████████

████████████████

████████████████

████████████████

████████████████

████████████████

████████████████

████████████████

Actually it should really even be far lower contrast than that as it is impractical to have even 50% MTF at Nyquist frequency as that would lead to too much visible but aliased (false) detail a little above Nyquist.

If anyone wants to experiment and has the image authoring software, they can create a 2-pixel chequerboard pattern [that is each square in the chequerboard is 2 pixels by 2 pixels] in 1920x1080 format, load it into a video authoring program that duplicates the still as frames in a video and then save the output as a 1920x1080 MPEG video (one of the codecs used for Blu-ray disks). The MPEG encoding parameters should be set to suit video.

They can then play the MPEG on a 1920x1080 digital display and inspect adjacent pixels. They will see light grey and dark grey. They will not see white and black; even very close to the screen. This has to do with sampling theory and the requirement for smooth video, and for avoiding aliasing.

It will no better if a Genesis camera is used instead of a pristine 960x540 square chequerboard created electronically, and it will probably be worse, i.e a lower MTF, but that would depend on the setting used on the camera and the format in which the output was archived prior to creation of the Blu-ray or HD-DVD disk.

Thanks Thudd, for your chequerboard analogy.

This is good theory but ignores the way these discs images are actually created. It is not as Black and white (pardon the pun) as your analogy and illustration show.

The point I am trying to make is that you have, for sake of argument, 4 million pixels in the film to digital source. The end result product will only contain 1 million pixels. Even if 50% of the pixels in the original are not good (grey globs) you still have more than enough perfect pixels to harvet for the end print.

And the above simple example I give likewise ignores all the post production and error correction done as well!

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a good post there bac, unfortunately as you say the data is quite old now 5-6 years old, and digital camera system have progressed a heap in that time let alone storage systems which quite liekly would have been a limitation back then. Imaging systems though have come a long way since, even with consumer cameras the cmos used in my 40d is a quantam leap up from the 10D from 4-5 years ago, and storage systems we now have means not even dreamed off back then !

I linked to that same document in my original post, but you obviously did not read it.

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I have provided plenty of evidence, but you I either did not read it or choose to ignore it.

My “theory” as you call it is based on all available evidence I can find, none of it is in contradiction.

~

we have not seen any evidence to support your theories, all we have seen is some fabrications of yours based on your own subjective opinion with no evidence put forward to back it up.

~

At no stage have I said that film is limited to 1902x1080 resolution. What I have consistently stated is that cinema film is not capable of providing 100% MTF at 1920 lines per picture width by 1080 lines per picture height, and I supplied multiple links to support that claim.

Please provide a link to just one film or digital camera that can provide 100% MTF at 1920 lines per picture width by 1080 lines per picture height. I have not been able to find any camera with such performance.

~

yes as I have provided links to info that clearly states film has a massive resolution and 100% mtf is not needed as 4k or 4 times that needed for 1920x1080 is a walk in the park and even 6k with camera and lens systems. We have not seen anything from you to indicate camera and film transfer sytems for movies cant output 1920x1080 resolution for hd dvd and blu ray.

~

The “Lowry Process” scans at 4000 pixel across the frame or double 1920.

The Nyquist limit is 2000 pixels and the typical MTF at the Nyquist limit is 20%.

Since the MTF of the system is the sum of MTF losses in the lens, film and scanner the MTF at 1920 will be much less then 20%.

~

we have not seen any evidence from you, on the lowry film scanning system, or any of the above to support that, all we have got is your personal opinion being pushed as fact without any evidence to back it up. o the other hand I have provided

http://www.cintel.co.uk/dlfiles/techdocs/E...0Resolution.pdf

shows film scanning at 4K for film provides more than enough information to achieve 1920x1080 for hd dvd and blu ray infact and what is used for 2K digital projectors and opens the door for 4K projection

~

Actually the Genesis down scales in the camera and only outputs 1920x1080, NOT 4k.

The Canon SLR I linked is exceptional, it is very close to the theoretical limits of a camera with a 16MP sensor (compared to the 12MP sensor in the Genesis) , and with digital sharpening even exceeds those limits at the expense of a little aliasing. Even then it is not capable of providing 100% MTF at 1920 lines per picture width by 1080 lines per picture height.

To exceed the performance of the Canon the genesis would need to defy the limitations of lenses and digital image capture. To get 100% MTF at 1920x1080 it would have to defy those real world limits by a HUGE margin.

Please provide a link to ANY camera that can do that, I cant find one anywhere.

~

so the fact the genesis cuts its 2K resolution in half for 1920x1080 for hd dvd and blu-ray is supposed to be a limitation that it cant acheive 1920x1080 ? what kind of poppycock argument is that. and anyways what evidence exactly have you provided on the genesis to suggest that says it cant output 1920x1080 for blu ray ? a link to a user handbook and a panavission web page :rolleyes:

comparisons with a digital slr are completely ridiculous, even mlx agreed on that. its completely ridiculous to talk of the limitations of a digital movie camera which you know nothign about by discussing a digital still slr, a completely different style of camera, usign different lenses, differnet imaging chips even made by completely different companies and with completly different abilities.

~

I never said the viewing distance calculators are irrelevant, you did. In fact I consider them conservative.

The best 1080 video does have some useful information out towards the pixel resolution limit, but that detail is so low in contrast that you need to be at least as close to the screen as viewing distance calculations recommend to see it.

so they are now not irrelevant. why is that so ?. on one hand you say we cant resolve 1920x1080, then what exactly is the point of you forcing it downs peoples throats for all this time tellign them to fuly resolve 1920x1080 information they must use the chart ?

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Yes Thudd, your example is a good illustration of the principles involved. If an attempt were made to transfer what the Genesis camera recorded onto a high definition disk (BR or HD-DVD) unfortunately there would be an expanse of grey, and possibly the faintest hint of a chequerboard pattern; unless the encoding for the Blu-ray or HD-DVD was set for text mode [not a normal mode, and not used for movies], rather than video mode.

Another, less demanding, example would be a 2-pixel chequerboard pattern. This would result in 960x540 squares. This is at the critical Nyquist limit. The original perfect chequerboard would look like this, as best I can repesent it by typing in characters and formatting the colour:

????????????????

????????????????

????????????????

????????????????

????????????????

????????????????

????????????????

????????????????

How the Blu-ray or HD-DVD authoring codec would encode this 960x540 pattern would be a lower MTF version resembling this:

????????????????

????????????????

????????????????

????????????????

????????????????

????????????????

????????????????

????????????????

Actually it should really even be far lower contrast than that as it is impractical to have even 50% MTF at Nyquist frequency as that would lead to too much visible but aliased (false) detail a little above Nyquist.

If anyone wants to experiment and has the image authoring software, they can create a 2-pixel chequerboard pattern [that is each square in the chequerboard is 2 pixels by 2 pixels] in 1920x1080 format, load it into a video authoring program that duplicates the still as frames in a video and then save the output as a 1920x1080 MPEG video (one of the codecs used for Blu-ray disks). The MPEG encoding parameters should be set to suit video.

They can then play the MPEG on a 1920x1080 digital display and inspect adjacent pixels. They will see light grey and dark grey. They will not see white and black; even very close to the screen. This has to do with sampling theory and the requirement for smooth video, and for avoiding aliasing.

It will no better if a Genesis camera is used instead of a pristine 960x540 square chequerboard created electronically, and it will probably be worse, i.e a lower MTF, but that would depend on the setting used on the camera and the format in which the output was archived prior to creation of the Blu-ray or HD-DVD disk.

Thanks Thudd, for your chequerboard analogy.

really ? and you have some actual evidence to back that up or is this somethign you fabricated as well ?

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I linked to that same document in my original post, but you obviously did not read it.

I actually was commenting on bacs post being a good one, I did read the same document as you posted but for the same reasons as below I dis regared it. digital technology has moved along way too fat in 5-6 years

a good post there bac, unfortunately as you say the data is quite old now 5-6 years old, and digital camera system have progressed a heap in that time let alone storage systems which quite liekly would have been a limitation back then. Imaging systems though have come a long way since, even with consumer cameras the cmos used in my 40d is a quantam leap up from the 10D from 4-5 years ago, and storage systems we now have means not even dreamed off back then !
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~

And the above simple example I give likewise ignores all the post production and error correction done as well!

actually I think if I remember hosko posted quite well on this early in this thread but he said the loses in post production is very little if any.

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sorry but what evidence exactly did owen produce that is evidence that the genesis cant output at 2K or twice that required for 1920x1080 for hd dvd and blu-ray. all we have seen him dismiss is evidence posted on the genesis capabilities and all he has put forward is his own summation and personal subjective view and opinion that I can see.

In the absence of any published MTF data for the Genesis camera I have been generous and assumed it has perfect theoretical response limited only by its sensor pixel count and Nyquist limits. Even under this perfect and unlikely scenario it cannot provide 100% MTF for its 1920x1080 output.

It uses the same lenses as Panavison film cameras and we can see from the info I have linked how much affect Panavision lenses have on the MTF response of film.

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In the absence of any published MTF data for the Genesis camera I have been generous and assumed it has perfect theoretical response limited only by its sensor pixel count and Nyquist limits. Even under this perfect and unlikely scenario it cannot provide 100% MTF for its 1920x1080 output.

It uses the same lenses as Panavison film cameras and we can see from the info I have linked how much affect Panavision lenses have on the MTF response of film.

yep just more personal opinion and fabricated theories rather than any actual evidence but what the heck it pushes your barrow :rolleyes:

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we have not seen any evidence to support your theories, all we have seen is some fabrications of yours based on your own subjective opinion with no evidence put forward to back it up.

yes as I have provided links to info that clearly states film has a massive resolution and 100% mtf is not needed as 4k or 4 times that needed for 1920x1080 is a walk in the park and even 6k with camera and lens systems. We have not seen anything from you to indicate camera and film transfer sytems for movies cant output 1920x1080 resolution for hd dvd and blu ray.

I don’t see any MTF graphs in the information you provided.

I have provided graphs from Kodak for raw film response in a lab without a camera or lens. I have also provided graphs from three different sources showing response of negative film used in a Panavision camera.

They all show that 100% MTF is not possible at high spatial frequencies. In fact the performance of the negative from a camera is heavily degraded at 1920 lines per picture width and 1080 lines per picture height. Response still exists to much higher spatial frequencies, but at quite low MTF.

If you have any hard data to refute this please post it.

we have not seen any evidence from you, on the lowry film scanning system, or any of the above to support that, all we have got is your personal opinion being pushed as fact without any evidence to back it up. o the other hand I have provided

http://www.cintel.co.uk/dlfiles/techdocs/E...0Resolution.pdf

shows film scanning at 4K for film provides more than enough information to achieve 1920x1080 for hd dvd and blu ray infact and what is used for 2K digital projectors and opens the door for 4K projection

I read that article months ago and it does not provide MTF data.

The issue has never been that there is no data at 1920x1080. Data does exist in film to high spatial frequencies and as long as MTF is above about 5-10% people call it resolved. However it is very blurred and only just perceptible at the limit. For film Red has dramatically lower response then Green or Blue.

The Lowry scanning system is limited by the same laws that govern ALL digital capture devices.

so the fact the genesis cuts its 2K resolution in half for 1920x1080 for hd dvd and blu-ray is supposed to be a limitation that it cant acheive 1920x1080 ? what kind of poppycock argument is that. and anyways what evidence exactly have you provided on the genesis to suggest that says it cant output 1920x1080 for blu ray ? a link to a user handbook and a panavission web page :rolleyes:

The Genesis cuts its sensor resolution by two thirds to output at 1920x1080. It will deliver good image detail at 1920x1080, almost certainly better then film, but NOT at 100% MTF, not EVER.

comparisons with a digital slr are completely ridiculous, even mlx agreed on that. its completely ridiculous to talk of the limitations of a digital movie camera which you know nothign about by discussing a digital still slr, a completely different style of camera, usign different lenses, differnet imaging chips even made by completely different companies and with completly different abilities.

so they are now not irrelevant. why is that so ?. on one hand you say we cant resolve 1920x1080, then what exactly is the point of you forcing it downs peoples throats for all this time tellign them to fuly resolve 1920x1080 information they must use the chart ?

Digital cameras are digital cameras, it makes no difference if it’s a Genesis or a high end SLR, the same rules apply.

Look at any digital camera MTF data and you will see the same sort of response, limited by pixel count and Nyquist laws.

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I suppose an audio analogy would be to ask whether a midrange speaker can reach 15KHz. Yes, there may be some audible output from the speaker at 15KHz, but it it is unlikely to be at the same level as the output at 1 KHz. If the speakers' response at 15 KHz is only half its response at 1 KHz, the speaker is deficient at 15KHz, although it does extend to that frequency.

Cheers.

Your analogy to audio is spot on mate.

With HD we effectively have the treble control turned down, the high frequencies are still there, but are hard to hear because the relative level is low in comparison the low frequencies.

Some of use want 20Hz to 20Khz response from our systems, but it seems others are happy with 20Hz to 15Kz -3db. :D

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I don’t see any MTF graphs in the information you provided.

I have provided graphs from Kodak for raw film response in a lab without a camera or lens. I have also provided graphs from three different sources showing response of negative film used in a Panavision camera.

They all show that 100% MTF is not possible at high spatial frequencies. In fact the performance of the negative from a camera is heavily degraded at 1920 lines per picture width and 1080 lines per picture height. Response still exists to much higher spatial frequencies, but at quite low MTF.

If you have any hard data to refute this please post it.

I read that article months ago and it does not provide MTF data.

The issue has never been that there is no data at 1920x1080. Data does exist in film to high spatial frequencies and as long as MTF is above about 5-10% people call it resolved. However it is very blurred and only just perceptible at the limit. For film Red has dramatically lower response then Green or Blue.

The Lowry scanning system is limited by the same laws that govern ALL digital capture devices.

The Genesis cuts its sensor resolution by two thirds to output at 1920x1080. It will deliver good image detail at 1920x1080, almost certainly better then film, but NOT at 100% MTF, not EVER.

Digital cameras are digital cameras, it makes no difference if it’s a Genesis or a high end SLR, the same rules apply.

Look at any digital camera MTF data and you will see the same sort of response, limited by pixel count and Nyquist laws.

so given you have no actual evidence to support your original claims, jsut some fragments from around the place that you have fabricated together along with yoru own subjective opinion, you then do admit that there is 1920x1080 resolution for hd dvd and blu ray.

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