Mtf Of Blu-ray/hd-dvds

[momaw]

its owen who was saying in the pio thread that 1080 displays were a waste as hddvd and bluray never have 1920x1080 resolution.

And that is all I have ever been arguing against. Even if we end up agreeing to disagree, all parties have accepted that CGI movies can have fully resolved 1920x1080 thus proving this position inaccurate.

[betty boop]

From the above link do you agree or disagree with the following statement ?

I couldnt say 100% is necessary to achieve 1920x1080 given the information I've seen and read for film or digital. and anyways even in the etconsult link its not like mtf readings necessarily translated to the visible resolution as observed by viewers in the tests they ran and that was even with the well recognised limitations of film projection systems.

[drsmith]

And that is all I have ever been arguing against. Even if we end up agreeing to disagree, all parties have accepted that CGI movies can have fully resolved 1920x1080 thus proving this position inaccurate.

Could you please provide a link.

[momaw]

Could you please provide a link.

how bouts I quote your own fearless leader

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.

[drsmith]

how bouts I quote your own fearless leader

I'm even more curious as to why you consider Owen to be my fearless leader.

[momaw]

I'm even more curious as to why you consider Owen to be my fearless leader.

Do you want links

[Felix..]

Do you want links

How about a link to his own sig. Another Sony SXRD mega fanboi I'm afraid, just like MLXX, coming to Owen's defence. Perhaps he should remove that reference as Owen was compelled to do.

[drsmith]

Do you want links

Do you agree with Felix ?

How about a link to his own sig. Another Sony SXRD mega fanboi I'm afraid, just like MLXX, coming to Owen's defence. Perhaps he should remove that reference as Owen was compelled to do.

[MLXXX]

how bouts I quote your own fearless leader

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.

Momaw, that only applies to a still image cgi of text or graphics, not a moving cgi, or a still cgi representing real life.

What MPEG2 processing can do

This afternoon I mentioned that even a chequerboard pattern with squares 2-pixels by 2-pixels would not be reproduced with 100% MTF.

Well I tried this half an hour ago and the result was a very weird pixelation approximation indeed:-

http://www.dtvforum.info/index.php?act=att...ost&id=3974

The image on the left is the chequerboard I created in paint shop pro (the levels for white and black were 235 and 16) on a grey background. The image on the right is captured from the full screen playback of a 1920x1080i video I created using Adobe Premier Pro, and with a trial version of the Mainconcept Pro MPEG encoder, set to 38.5 Mbps.

Different codecs would produce different results but most codecs would be expressly designed to aim for no greater than 960x540 visible resolution, when handling frames of 1920x1080 pixels; in order to avoid aliasing difficulties.

If it were really important to present a static cgi with features requiring 1 pixel resolution (e.g. an architectural CAD static image) on a Blu-ray disk, it might be possible to alter some of the settings of the MPEG encoder so that it would not filter or average but allow the image to pass unscathed and intact; and hopefully the mpeg2 decoder would decode faithfully. This however would be a very specialised use, and far removed from the core subject matter of this thread. This thread concerns itself with the MTF of Blu-ray and HD-DVD movies, as derived from cameras used to capture real-life images.

Edited October 4, 2007 by MLXXX

[Autocrat]

It needs to be said: Al and momaw, you're talking out of your arses. You clearly don't know what you're talking about, and you are both out of your depth in this discussion, seemingly content to try and score points with pissy debating tactics or personal swipes, instead of actually arguing a technical case.

What's more, it's really really obvious.

And, Al, it's "acuity", not "aquity". It doesn't help your case that you can't spell the thing you're arguing against.

Give it a rest, you've lost the battle. Perhaps sit back and learn something.

[momaw]

It needs to be said: Al and momaw, you're talking out of your arses. You clearly don't know what you're talking about, and you are both out of your depth in this discussion, seemingly content to try and score points with pissy debating tactics or personal swipes, instead of actually arguing a technical case.

What's more, it's really really obvious.

And, Al, it's "acuity", not "aquity". It doesn't help your case that you can't spell the thing you're arguing against.

Give it a rest, you've lost the battle. Perhaps sit back and learn something.

Whatever you say. The pm's of support I have received seem to indicate otherwise, but hey, you're the expert right.

What is clear is you guys don't actually have any idea of the processes involved in creating HD DVD/Blu-ray masters. That is the argument I am having. I've even extended the invitation to take it to the experts who actually create these masters, but that was declined. Wonder why?........ I'm all for learning, it is why I am here. And I have learn't alot more about the capture process from this thread, but I am talking about the processes way down the line that everyone else seems content to ignore.

Personal swipes.....hello pot, the kettle is calling.

[Autocrat]

Just keep on doing what you're doing. It's funny.

[betty boop]

It needs to be said: Al and momaw, you're talking out of your arses. You clearly don't know what you're talking about, and you are both out of your depth in this discussion, seemingly content to try and score points with pissy debating tactics or personal swipes, instead of actually arguing a technical case.

What's more, it's really really obvious.

And, Al, it's "acuity", not "aquity". It doesn't help your case that you can't spell the thing you're arguing against.

Give it a rest, you've lost the battle. Perhaps sit back and learn something.

really good to see your very valued contribution to this discussion "autocrat" how I spell anything is not for your benefit whether I spell it acuity or aquity I really dont give a sh!t and neither is that the topic of discussion, but now you mention it davep as you have no doubt still is waiting for an answer to that little question from owen back here in case its kinda(oh look I misspelkt here for your little benefit for our little autcratic friend hehe) forgotten

Whats more important - the # of pixels on the screen, or the amount of information? If it's the latter, why are there HD screens (again discounting PC use and CGI cartoons etc)? Also, if there is only a maximum of "960x540 individual "pieces" of information", why are viewing distances for 1080 panels scrutinised, when chances are 95% of the time, people watching HD TV (even shows filmed in HD), and/or HD DVD/Blu-ray (actually, I won't guess. In MY case, 95% of viewing is TV/film)?

and by the way talking out your @rse ?, that was actually what drove this discussion in the first place. And to me it is plainly obvious and demonstrated clearly here how people without a clue of what theyre talking about fabricate theories with unrelated shreds of info cobbled together with their own personal opinion and trying to push forward as the truth. We've seen it here with owen trying to pass judgement on the genesis camera on basis of a digital slr still cameras abilites and condemn the genesis capabilities while admitting to having no info on it and yet without having no further evidence on it but a web link to the panavission web page and a faq list !

our friend here mlx ? you just have to have a read of the text in his opening to see he had no clue and we have not seen one shred of real and actual evidence from him to back up his claims. all we got from was some sh!t he made up as he went along following in owens footsteps, which ended up even contradicting himself and even owen and getting all a bit muddled up.

myself all I put up was info disputing their claims, all I asked was evidence from them backing up their claims and disputing the information I had contradicting what they said. we got neither, all we got in return was some BS which is really quite typical now and all we can expect from this lot.

it was all a bit pathetic quite frankly. people talkign out their @rse ? I know who they are and this thread quite frankly well and trully confirmed it !

[betty boop]

Whatever you say. The pm's of support I have received seem to indicate otherwise, but hey, you're the expert right.

What is clear is you guys don't actually have any idea of the processes involved in creating HD DVD/Blu-ray masters. That is the argument I am having. I've even extended the invitation to take it to the experts who actually create these masters, but that was declined. Wonder why?........ I'm all for learning, it is why I am here. And I have learn't alot more about the capture process from this thread, but I am talking about the processes way down the line that everyone else seems content to ignore.

Personal swipes.....hello pot, the kettle is calling.

well said mo

[momaw]

Ok, since you guys pretty much point blank refused to take this to the experts I have.

Here is Amir has to say:

Let's clear some things first. The formats most definitely can resolve 1920x1080. There are already test discs with test patterns of this resolution which fully resolve on a number of displays which support this resolution (with 1:1 pixel mapping).

So perhaps they are talking about weakness in another part of the chain. At the source, if the material is shot on 35mm film, there is absolutely no problem to match or exceed this resolution. My 35mm lenses at least in the center resolve enough for my 16 megapixel camera. 1080p is only 2 megapixels so even cheap lenses would have no problem there. Now, the MTF of wide angle lenses is much worse than telephoto but even there we can resolve well above 2 megapixels.

Maybe they are talking about telecine process? If so, we can already scan at higher resolutions than "2K" so I don't see that as a limitation either.

So all in all, it is not a valid argument. The source exceeds the resolution of the format and the format itself can pass through 1920x1080.

There you go. The formats do fully resolve 1920x1080 even from film sources.

You are all welcome.

[Autocrat]

Here's a link you should come to love and understand.

[momaw]

Here's a link you should come to love and understand.

Nice contribution. Guess you don't like my previous post.

[betty boop]

Ok, since you guys pretty much point blank refused to take this to the experts I have.

Here is Armin has to say:

There you go. The formats do fully resolve 1920x1080 even from film sources.

You are all welcome.

well done mo look forward to reading what comes up it

[toastie1503561419]

I think there's a lot of confusion about resolving pixels on the screen.

Here's how I think of it:

There are multiple stages involved in getting a live image to your display.

Live -> Camera -> transfer process -> HD/Blu-ray -> Display

The last step disc transfers to the 1080p screen exactly. Here there is a 1:1 mapping of pixels in this stage. No debate about this.

Where the debate seeems to be occuring (and the issue of MTF arises) is in the capture of live images through a camera. The process of recording live (as in real people acting etc) results in some loss because of the sampling/filter technology used. There is no 1:1 mapping here - a pixel on the recorded image does not correspond to a single element of the images being recorded. MTF and smapling means that a pixel on the recorded image represents a sample of the actual scene. This is the loss that Owen and MLXX are talking about when they are talking about the resolution being recorded and MTF. What they are saying is that with current technology, there is no 1920x1080 recording, even with higher resolutions used in profession digital movie cameras.

Am I on the right track here?

(note - None of this is the case with CGI since the 'camera' stage is actually a computer generated scene at exactly 1920x1080.)

[betty boop]

I think there's a lot of confusion about resolving pixels on the screen.

Here's how I think of it:

There are multiple stages involved in getting a live image to your display.

Live -> Camera -> transfer process -> HD/Blu-ray -> Display

The last step disc transfers to the 1080p screen exactly. Here there is a 1:1 mapping of pixels in this stage. No debate about this.

Where the debate seeems to be occuring (and the issue of MTF arises) is in the capture of live images through a camera. The process of recording live (as in real people acting etc) results in some loss because of the sampling/filter technology used. There is no 1:1 mapping here - a pixel on the recorded image does not correspond to a single element of the images being recorded. MTF and smapling means that a pixel on the recorded image represents a sample of the actual scene. This is the loss that Owen and MLXX are talking about when they are talking about the resolution being recorded and MTF. What they are saying is that with current technology, there is no 1920x1080 recording, even with higher resolutions used in profession digital movie cameras.

Am I on the right track here?

(note - None of this is the case with CGI since the 'camera' stage is actually a computer generated scene at exactly 1920x1080.)

hi toastie, no confusion here along those lines. thudd was under that impression as well but I responded to him with this post earlier

I agree thudd, ofcourse thats the case, and I am certaily not suggesting that film or digital cameras start of with a 1920x1080 resolution and thats what they deliver and certainly I am not sayign that cameras be they film or digital have the almost infinite resoltuion capability required to portray the organic real world life forms and surfaces around us. after all look at any what might appear to our eyes as flat surfaces look with a higher resolving device and you will soon notice hills and valleys and crevaces.

but for the purposes of this discussion, the information I've seen so far certainly indicates film & digital cameras are certainly capable of capturing very high resolution images, 4K for film, 2-4K for HD digital. which is quite sufficient for a 1920x1080 resolution image for hd dvd & blu-ray even allowing for losses along the way, given the 2-4 times amount of resolution in the intial image captured.

if you read that etconsult link, thats what its sayign too which makes sense.

and good on you for agreeing there is no argument with cgi unless a few here who seem to still contend with their own made arguments.

ps in concerns your opening statement,

I think there's a lot of confusion about resolving pixels on the screen.

this discussion not about resolving pixels on screen but your right owen and mlx's statements have created confusion since now they are contending there isnt 1920x1080 possible on screens because of source, and quite rightly the likes of davep have questioned this as as to the need of the aquity charts and viewing distances in that case that has forever been contended as sacred to ensure we can resolve 1920x1080 !.

also additionally re mtf charts you'll see there is not a lot of corelation between what the charts say is fully resolved vs the viewers observed resolution, in the tests done in that etconsult link and thats bearing in mind that was with any old film not necessarily the best used for the blockbusters and also the well recognised limitations of film projection including the level of technology given the tests were done now 5-6 years ago.

ps I mentioned IMAX at the start of this thread, there are many imax titles on blu ray and hd dvd is there contention on these too that they do not actually contain 1920x1080 resolution ?

[drsmith]

How about a link to his own sig. Another Sony SXRD mega fanboi I'm afraid, just like MLXX, coming to Owen's defence. Perhaps he should remove that reference as Owen was compelled to do.

I'm not sure what rock you crawled out from under, but if the above is reflective of your standard of contribution I suggest you crawl back under it.

Nice contribution. Guess you don't like my previous post.

Your motivation in thts thrad is quiet obvious and it's not to engage in constructive discussion.

I don't know why Owen and MLXXX are wasting so much their time with your nonsense.

[MLXXX]

Whats more important - the # of pixels on the screen, or the amount of information? If it's the latter, why are there HD screens (again discounting PC use and CGI cartoons etc)? Also, if there is only a maximum of "960x540 individual "pieces" of information", why are viewing distances for 1080 panels scrutinised, when chances are 95% of the time, people watching HD TV (even shows filmed in HD), and/or HD DVD/Blu-ray (actually, I won't guess. In MY case, 95% of viewing is TV/film)?

Good questions, DaveP.

The simple fact of the matter is that in order to transmit 960x540 distinctly resolvable lines of information that are not constrained in their smooth movement, you need to carry that information by way of at least 1920x1080 samples.

It's similar to audio CDs, which use a sample frequency of 44.1KHz but can only carry audio frequencies up to 22.05KHz (or a little less because of the need for filtering to avoid aliasing). Aliasing with audio manifests itself as spurious tones at a much lower frequency. It is totally unacceptable and gross. A little bit of aliasing with video is not as bad but needs to be kept at a low level or the image will look artificial and strange patterns are created.

Coming back to your question about a digital display, we again need at least 1920x1080 sample points in order to reproduce 960x540 distinctly resolvable lines that can smoothly move across the screen [and are not aligned with pixel locations like computer text].

So there is no swifty being pulled by the panel manufacturers.

I should mention that it is sometimes suggested that rather than a 2:1 ratio, more like a 3:1 ratio or even greater should be observed between the number of sampling points (picture elements or pixels) and the underlying resolvable lines of the image. I suspect that a lot of high-definition disks are using filtering to keep the resolvable lines to somewhat less than 960x540 and this makes for a very smooth image, though it is a little on the soft side. Still streets ahead of conventional DVDs though!

In addition to what I've said above, which is all about sampling, there are further reasons why the contrast or MTF is not good as we approach 960x540 and that is because even film negatives measurably taper off (especially in their response to red) at this 'lowly' definition; depite the fact that they give some response out to much higher spatial frequencies. When the film emulsion is exposed to a narrow stream of photons [assuming for the sake of argument a perfect lens] the chemical reaction spreads slighty beyond where the stream of photons strikes the emulsion. The later chemical process of developing the negative, causes further spreading. 35mm film stock is probably only just big enough for the 1920x1080 digital format. I myself would prefer larger film stock to be used, if a movie is to be captured using film.

Edited October 5, 2007 by MLXXX

[betty boop]

I'm not sure what rock you crawled out from under, but if the above is reflective of your standard of contribution I suggest you crawl back under it.

Your motivation in thts thrad is quiet obvious and it's not to engage in constructive discussion.

I don't know why Owen and MLXXX are wasting so much their time with your nonsense.

and your contribution to this thread doc ? or are you part of the harem as well ?

[momaw]

Your motivation in thts thrad is quiet obvious and it's not to engage in constructive discussion.

My motivation is to dispel a piece of FUD regarding the capabilities of Blu-ray and HD DVD. I have now done that. If you don't like that, that is your choice.

[Autocrat]

ps in concerns your opening statement,

this discussion not about resolving pixels on screen but your right owen and mlx's statements have created confusion since now they are contending there isnt 1920x1080 possible on screens because of source,

Read it this time. The first paragraph is about the most concise and accurate representation of the error that I've seen.