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Mtf Of Blu-ray/hd-dvds


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The problem is the MTF at that solution. Please provide just one example of any camera that can provide 100% MTF at 1920 lines per picture width or 1080 lines per picture height.

you obviously didnt read the link as its quite clear what it says, 4k is a walk in the park and 6k is quite possible, can you understand that. and that is from cintel who actually know a lot more abotu these things than you ever will. Given this massive resoltuion 100% mtf is neither required or necessary.

did you ever ask yourself why the lowry scans are done at 4K ? have a good hard think about it !

and by the way your the one supposed ot provide mtf data on cameras such as the geneis to back up yur claims, we're still waiting.

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I have always maintained that the ONLY way to get 100% MTF at 1902x1080 is with computer generated images, (provided they have not been scaled). Unless we are only viewing CGI only content, 100% MTF images are not posible.

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so you agree CGI movies on hd dvd and blu ray can have 1920x1080 resolution ? and as indicated for non computer generated images given the massive capability 100% mtf is neither required or necessary

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The Visual acuity model on which viewing distance calculators are based have proved to be very accurate in my experience with 1:1 pixel mapped computer generated test paterns. They are based on perfect video source with 100% MTF at the resolution specified, a situation that cannot exist in practice for none computer generated content.

Video never has the resolution its pixel count would suggest, so longer viewing distances can be use without perceptible loss of visible resolution.

you perhaps need ot explain that to mlx as he is completely under some other aprehension. so lets get this right, for all these displays for which you've been ramming down peoples throat that they need to sit with their noses to the screen, and get massive display sizes, unless they watch computer genrated images they dont need to sit at the distances you've been telling them and dont need to get the massive screens you've been telling them to get ?

why did you get such a big display, why did you get a 1920x1080 capable display ? why do you sit so close to the display as per the visual aquity charts after all unles its computer generated there is no need to is there ...accordign to your misguided self.

so you going to tell everyone on the viewing distance sticky? or do I need to? that you have been misleading them all this time ?

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The film negative from a Panavisoon camera cant provide 1920 lines per picture width by 1080 lines per picture height at 100% MTF, not even close, so how on earth is a HDDVD or BluRay disk mastered from that negative going to achieve it?

Movies are not filmed at 1920x1080. How many times does this need to be repeated. As to the rest, I think Al has pretty much summed it up perfectly above.

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you obviously didnt read the link as its quite clear what it says, 4k is a walk in the park and 6k is quite possible, can you understand that. and that is from cintel who actually know a lot more abotu these things than you ever will. Given this massive resoltuion 100% mtf is neither required or necessary.

A notional quoted 4k or 6k resolution is useless without an accompanying MTF graph.

Kodak provide such graphs for a reason, and they show 1920x1080 at 100% MTF is not possible even in the lab without a camera or lens.

did you ever ask yourself why the lowry scans are done at 4K ? have a good hard think about it !

4k scans are used because they are needed to partly mitigate the Nyquist sampling limits of digital acquisition. The output of a 4k scanner has higher MTF then a 2k scanner, but NEVER 100% at 1920x1080.

and by the way your the one supposed ot provide mtf data on cameras such as the geneis to back up yur claims, we're still waiting.

so you agree CGI movies on hd dvd and blu ray can have 1920x1080 resolution ? and as indicated for non computer generated images given the massive capability 100% mtf is neither required or necessary

I have been unable to find any MTF data on the Genesis camera, it you can please post it here.

As it stands I see no reason why the Genesis will defy mathematical laws governing digital acquisition and magically do what no other digital camera can, even ones with much greater pixel counts then the Genesis.

Maybe you don’t consider a black pixel in the original image displayed as grey on screen and an adjoining black pixel displayed as dark grey due to poor MTF is not significant, but I do.

you perhaps need ot explain that to mlx as he is completely under some other aprehension. so lets get this right, for all these displays for which you've been ramming down peoples throat that they need to sit with their noses to the screen, and get massive display sizes, unless they watch computer genrated images they dont need to sit at the distances you've been telling them and dont need to get the massive screens you've been telling them to get ?

If people want to be able to see 1080 resolution, the viewing distances recommended by the human visual acuity model viewing charts need to be followed. The fact that HD video from any source never has 100% MTF at 1920x1080 is a separate issue, and is the reason 720p displays can compete with 1080 display at normal viewing distances.

Good 1080 source is better the good 720p source no question, its easy to see if you sit close enough, but 100 % MTF 1080 source would be much better again.

Then there is the issue of theatrical presentation to THX recommended standards which require a very large screen to be viewed up close, so close that a 720p display looks ordinary.

why did you get such a big display, why did you get a 1920x1080 capable display ? why do you sit so close to the display as per the visual aquity charts after all unles its computer generated there is no need to is there ...accordign to your misguided self.

I got a 70” display because my previous 57’ was too small for movies at 2.8 meters, the maximum recommended viewing distance for THX certified movie viewing on a screen that size. (26 degrees viewing angle)

The 70” provides a 31 degree viewing angle at 2.8 meters, short of the recommended 36 degrees for THX presentation. At that size- distance a display of less then 1080 is not an option.

As it stands 2.35:1 wide aspect movies are still too small, and I would like an 80” display if I could get one. It would give me the required 36 degree viewing angle for proper THX certified movie presentation at 2.8 meters viewing distance.

1920x1080 resolution is not really adequate for this scenario, but it still looks very good if well mastered.

so you going to tell everyone on the viewing distance sticky? or do I need to? that you have been misleading them all this time ?

No, you do whatever you what; you will anyway I’m sure.

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Movies are not filmed at 1920x1080. How many times does this need to be repeated. As to the rest, I think Al has pretty much summed it up perfectly above.

No its not, but that’s not relevant.

Film resolution is expressed in Line pairs or cycles per mm. Convert that to lines per picture width-height and it is easy to see from Kodak’s data sheets that 1920 lines by 1080 lines at 100% MTF is not possible on cinema film stock. Lenses and subsequent digitization degrade the situating even further.

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I'm not participating in the various exchanges tonight. Owen seems to be handling that quite capably. But I thought I'd mention my own experiences with viewing distance:-

The Visual acuity model on which viewing distance calculators are based have proved to be very accurate in my experience with 1:1 pixel mapped computer generated test paterns. They are based on perfect video source with 100% MTF at the resolution specified, a situation that cannot exist in practice for none computer generated content.

Video never has the resolution its pixel count would suggest, so longer viewing distances can be use without perceptible loss of visible resolution for video sources.

My usual viewing distance for 1080 free to air material on my 60" 1920x1080 SXRD screen is 2.6m or if it is very detailed and good quality, 2.5m. Looking at alanh's chart at the beginning of the pinned thread on viewing distance for a 150cm diagonal (and for viewing 1080 material) I see it is 2.6m; so the chart works accurately for me. My vision when wearing spectacles is somewhat better than 20/20 [as tested just a few months ago when I got a new prescription].

Interestingly, if I display a 1 pixel 100% MTF pattern on my SXRD I can resolve it at 2.6m but it is more comfortably clear at 2.5m.

So for me I don't sit further away for good quality 1080 video than for 100% MTF 1-pixel graphics. Presumably my eyes prefer to see all that the display pixels have to offer, in order to be able to extract the maximum content; even though that content is well below 1920 visible resolution, and at a low MTF to boot.

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No its not, but that’s not relevant.

Film resolution is expressed in Line pairs or cycles per mm. Convert that to lines per picture width-height and it is easy to see from Kodak’s data sheets that 1920 lines by 1080 lines at 100% MTF is not possible on cinema film stock. Lenses and subsequent digitization degrade the situating even further.

Once again your "evidence" is completely irrelevant. 1920x1080 blu-ray/HD DVD studio masters are created from digital 4k sources. There is no film stock used in their creation or storage. They exist solely in the digital realm. If you were dealing with a straight from camera to disc process, you would have a point. But we are talking about a 4k master being transfered to a much smaller format with a high degree of "correction" to remove any the these issues. MTF is simply not an issue (except in the example I gave in a previous post - re less than HD captured source material) when it come to Blu-ray/HD DVD transfers. Again if we were talking bit for bit copies of the master (assuming Post Production hasn't corrected the issues) you may have a point, however the ability of the human eye to resolve the resolution on "home sized" screens more be a larger limiting factor.

Everything in this post has been said elsewhere in this thread.

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1920x1080 blu-ray/HD DVD studio masters are created from digital 4k sources. There is no film stock used in their creation or storage. They exist solely in the digital realm.

That is not entirely true - a significant number of Studio Masters are created from negatives...film is still used in a large proportion of movies.

Early parts of this discussion focussed extensively on the Lowry process which is specifically about the process of scanning a negative in order to make a new digital master.

Even in the case of Movie cameras with 4K digital backs there are issues - I was recently reading a technical discussion at a movie production site (I will supply the link later) where they talked about the practical impossibility of shining a light through a lens an illuminating a single pixel.

What they discussed was a "halo effect" where lighting a single "pixel" (which is actually a group of smaller sub components) would result in falloff of illumination up to 2-3 pixels away - even with the best available prime lens.

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A notional quoted 4k or 6k resolution is useless without an accompanying MTF graph.

Kodak provide such graphs for a reason, and they show 1920x1080 at 100% MTF is not possible even in the lab without a camera or lens.

~

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.

oh and by the way even mlx agreed with me ...so you have some convincing to do..where is the evidence to say otherwise ?

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Alebonau is correct in saying that negatives can contain more than sufficient detail for 1920x1080 Blu-ray/Hd-DVDs. ~

though not sure he knows what he's talking about.

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4k scans are used because they are needed to partly mitigate the Nyquist sampling limits of digital acquisition. The output of a 4k scanner has higher MTF then a 2k scanner, but NEVER 100% at 1920x1080.

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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.

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I have been unable to find any MTF data on the Genesis camera, it you can please post it here.

As it stands I see no reason why the Genesis will defy mathematical laws governing digital acquisition and magically do what no other digital camera can, even ones with much greater pixel counts then the Genesis.

~

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

http://en.wikipedia.org/wiki/Genesis_(Panavision)

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.

~

Maybe you don’t consider a black pixel in the original image displayed as grey on screen and an adjoining black pixel displayed as dark grey due to poor MTF is not significant, but I do.

If people want to be able to see 1080 resolution, the viewing distances recommended by the human visual acuity model viewing charts need to be followed. The fact that HD video from any source never has 100% MTF at 1920x1080 is a separate issue, and is the reason 720p displays can compete with 1080 display at normal viewing distances.

Good 1080 source is better the good 720p source no question, its easy to see if you sit close enough, but 100 % MTF 1080 source would be much better again.

Then there is the issue of theatrical presentation to THX recommended standards which require a very large screen to be viewed up close, so close that a 720p display looks ordinary.

I got a 70” display because my previous 57’ was too small for movies at 2.8 meters, the maximum recommended viewing distance for THX certified movie viewing on a screen that size. (26 degrees viewing angle)

The 70” provides a 31 degree viewing angle at 2.8 meters, short of the recommended 36 degrees for THX presentation. At that size- distance a display of less then 1080 is not an option.

As it stands 2.35:1 wide aspect movies are still too small, and I would like an 80” display if I could get one. It would give me the required 36 degree viewing angle for proper THX certified movie presentation at 2.8 meters viewing distance.

1920x1080 resolution is not really adequate for this scenario, but it still looks very good if well mastered.

~

perhaps you need to explain this to mlx who as mentioned was under a completely different aprehension,

~

Short answer: the charts for viewing televison video already take the limitation into account.

Longer answer:

The viewing distance charts were principally developed based on principles of human vision, and by actual use have been confirmed to work.

Real world video in a 1920x1080 pixel format (the format used by Blu-ray, HD-DVD, and some of the free to air high-definiton digital channels) never ever contains 1920xx1080 fully resolved lines of resolution, as explained earlier in this thread.

This is normal, standard, and par for the course.

Accordingly, the viewing distance charts would already take this characteristic into account [whether by explicit design, by empirical testing, or perhaps a bit of both; depending on who designed the chart].

but then again as I mentioned, not really sure he knows what he's talking about :wacko:

~

I have been unable to find any MTF data on the Genesis camera, it you can please post it here.

As it stands I see no reason why the Genesis will defy mathematical laws governing digital acquisition and magically do what no other digital camera can, even ones with much greater pixel counts then the Genesis.

Maybe you don’t consider a black pixel in the original image displayed as grey on screen and an adjoining black pixel displayed as dark grey due to poor MTF is not significant, but I do.

If people want to be able to see 1080 resolution, the viewing distances recommended by the human visual acuity model viewing charts need to be followed. The fact that HD video from any source never has 100% MTF at 1920x1080 is a separate issue, and is the reason 720p displays can compete with 1080 display at normal viewing distances.

Good 1080 source is better the good 720p source no question, its easy to see if you sit close enough, but 100 % MTF 1080 source would be much better again.

Then there is the issue of theatrical presentation to THX recommended standards which require a very large screen to be viewed up close, so close that a 720p display looks ordinary.

I got a 70” display because my previous 57’ was too small for movies at 2.8 meters, the maximum recommended viewing distance for THX certified movie viewing on a screen that size. (26 degrees viewing angle)

The 70” provides a 31 degree viewing angle at 2.8 meters, short of the recommended 36 degrees for THX presentation. At that size- distance a display of less then 1080 is not an option.

As it stands 2.35:1 wide aspect movies are still too small, and I would like an 80” display if I could get one. It would give me the required 36 degree viewing angle for proper THX certified movie presentation at 2.8 meters viewing distance.

1920x1080 resolution is not really adequate for this scenario, but it still looks very good if well mastered.

No, you do whatever you what; you will anyway I’m sure.

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.

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That is not entirely true - a significant number of Studio Masters are created from negatives...film is still used in a large proportion of movies.

Early parts of this discussion focussed extensively on the Lowry process which is specifically about the process of scanning a negative in order to make a new digital master.

Even in the case of Movie cameras with 4K digital backs there are issues - I was recently reading a technical discussion at a movie production site (I will supply the link later) where they talked about the practical impossibility of shining a light through a lens an illuminating a single pixel.

What they discussed was a "halo effect" where lighting a single "pixel" (which is actually a group of smaller sub components) would result in falloff of illumination up to 2-3 pixels away - even with the best available prime lens.

bris, mo was talking of digital fim cameras in that post and I provided a link to the genesis and many other cameras quite capable of outputing 4K.

http://en.wikipedia.org/wiki/Genesis_(Panavision)

and please read the cintel info I provided, you'll see the procesquite capable of 4K as is the lowry process

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

http://www.ezydvd.com.au/g/i/s/Videofuturelowryprocess.pdf

and a 4K capable camera has 4 times the necessary resoltuion for 1920x1080.

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That is not entirely true - a significant number of Studio Masters are created from negatives...film is still used in a large proportion of movies.

As al said r.e. Digital capture, and, my point was that the negatives are then used to create 4k masters which are then used to create 1920x1080 masters. The amount of information in a 4k master is more than adequate to create a much lower resolution 1920x1080 HD DVD/Blu-ray master which does not suffer from these initial capture issues. There is also the level of post production in "cleaning up" these issues.

If the guys had bothered to read up on Al's Lowry process info they would know what is going on, but I suspect they are too entrenched in their position to concede that their arguments (which they initially based on Digital SLR photography and not even motion picture production) are not relevant.

Hell now we have someone saying he sits at home watching the individual pixels on his screen and observing MTF in adjacent pixels :wacko:

Evidence (provided by al) has been ignored or refuted with evidence relating to digital still photography (yes same principle but the Movie process doesn't stop at the click of the shutter lens) and personal anecdotal subjective evidence that frankly is ludicrous. They also ignore invitations to discuss the issues with the experts, nor do they adress the points raised by someone (hosko) who clearly knows more than the rest of us here.

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If the guys had bothered to read up on Al's Lowry process info they would know what is going on, but I suspect they are too entrenched in their position to concede that their arguments (which they initially based on Digital SLR photography and not even motion picture production) are not relevant.

I'm not going to get into the argument, but there's some quite good reading on film v digital here: http://www.clarkvision.com/imagedetail/scandetail.html - the whole site is quite informative.

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I'll repond to a matter Alebonau raised as an apparent contradiction to Owen's position. I had stated: "Alebonau is correct in saying that negatives can contain more than sufficient detail for 1920x1080 Blu-ray/Hd-DVDs."

There is a difference between having sufficient detail and having sufficient MTF.

The 1920x1080 digital format does not concern itself with horizontal detail beyond 960 lines. Negatives contain detail beyond 960 lines. Ergo, negatives contain more than sufficient detail!

However, the key message has been missed: the quality of that detail. It is not as high in contrast (or MTF) as it could be. The response to the colour red at 960 lines is only 50% MTF for typical low speed 35mm film, as per the graph at Figure 11 on page 11 of a Sony pdf Owen referred to yesterday afternoon, and which I recommended as worth reading if only one of Owen's references were to be read.

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.

I am not going to spend more of my time presenting and re-presenting the same explanations. If the propositions are not understood or accepted by now, so be it.

Cheers.

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I'll repond to a matter Alebonau raised as an apparent contradiction to Owen's position. I had stated: "Alebonau is correct in saying that negatives can contain more than sufficient detail for 1920x1080 Blu-ray/Hd-DVDs."

There is a difference between having sufficient detail and having sufficient MTF.

The 1920x1080 digital format does not concern itself with horizontal detail beyond 960 lines. Negatives contain detail beyond 960 lines. Ergo, negatives contain more than sufficient detail!

However, the key message has been missed: the quality of that detail. It is not as high in contrast (or MTF) as it could be. The response to the colour red at 960 lines is only 50% MTF for typical low speed 35mm film, as per the graph at Figure 11 on page 11 of a Sony pdf Owen referred to yesterday afternoon, and which I recommended as worth reading if only one of Owen's references were to be read.

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.

I am not going to spend more of my time presenting and re-presenting the same explanations. If the propositions are not understood or accepted by now, so be it.

Cheers.

yes well you obviously miss the point about the massive resolution of film

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

The maximum resoluton of film

Firstly, the film format, 35mm can accomodate 6K resolution. Secondly the quality of taking lens has a dramatic effect on resolution. While today's zoom lenses are extremely good, the ultimate quality can often only be achieved with prime lenses. Good prime lens can acheive a solid 4K on the film and still resolve some information at 6K.

and to satisfy your 35mm digital still obsession

http://pic.templetons.com/brad/photo/pixels.html

How many pixels are there in even a 35mm frame of film

The very short answer is that there are around 20 million "quality" pixels in a top-quality 35mm shot. That's a shot with a tripod, mirror-up, with a top-rate lens and the finest-grained film, in decent light. 12 million are more typical for "good" shots. There may be as few as 4 million "quality" pixels in a handheld shot with a point-and-shoot camera or camera with a poor lens. And of course if focus is poor, or light is poor, or the camera was not held steady, the number will drop down below the 1-2 million pixels of the modern consumer digicam. Of course, one can have a bad shot with a digital camera too, not using all its resolving ability. However, few pick their gear with the plan of shooting badly.

so even with a 50% mtf 1920x1080 is still a walk in the park

and yeah anyways none of that for film or for that matter disputes digital movie camera or cgi capabilities which has been mentiones many times now are also source for hd dvd and blu-ray today. your original premise that it is not possible to get 1920x1080 onto hd dvd or blu-ray, is jsut plain wrong and we havent see nanything from you or anyone else as evidence to say any different.

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your original premise that it is not possible to get 1920x1080 onto hd dvd or blu-ray, is jsut plain wrong and we havent see nanything from you or anyone else as evidence to say any different.

And thats the crux of the matter you guys have been ignoring. The counter arguments and "evidence" are simply not relevant to the final HD DVD/Blu-ray product.

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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.

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I don't have a dog in this race, but from an objective viewpoint there's a couple of you guys making arses of yourselves.

Well said. :)

I wonder if the "silent observers" amongst us agree on who? Or is it whom? :unsure::blink:

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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

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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

What Al and I are saying it that there are enough fully resolved pixels in 4k masters (post production) to ensure all pixels in a 1920x1080 blu-ray/HD DVD print are fully resolved. That is not to say this always happens as care taken in the transfer, image manipulation, original source quality and other factors are also in play.

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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

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Once again your "evidence" is completely irrelevant. 1920x1080 blu-ray/HD DVD studio masters are created from digital 4k sources. There is no film stock used in their creation or storage. They exist solely in the digital realm. If you were dealing with a straight from camera to disc process, you would have a point. But we are talking about a 4k master being transfered to a much smaller format with a high degree of "correction" to remove any the these issues. MTF is simply not an issue (except in the example I gave in a previous post - re less than HD captured source material) when it come to Blu-ray/HD DVD transfers. Again if we were talking bit for bit copies of the master (assuming Post Production hasn't corrected the issues) you may have a point, however the ability of the human eye to resolve the resolution on "home sized" screens more be a larger limiting factor.

Everything in this post has been said elsewhere in this thread.

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.

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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.

I never said film stock is not used for original capture.

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