HDR is crayons

[Geoff D]

A 10-bit 2K master of a 2hr movie will clock in at 2TB. A 10-bit 4K master will be 8TB. Lowry use a special process to analyse and enhance their transfers which is why it needs so much bandwidth to process, but the final master would be the same size as those just mentioned.

At best we're looking at maybe 80 or 90GB of 4K video on a 100GB disc, leaving room for audio, menus and whatnot. 8TB into 90GB doesn't take a genius to work out, these discs are MASSIVELY compressed from the original so when people talk about it being a virtual copy of the negative or whatever then I wouldn't take it so literally. What they are saying is how fantastic it looks.

[Moonlight Shadow]

Restoration expert Torsten Kaiser is also opposed to the use of HDR for older movies. His very detailed explanation can be found here:

https://m.facebook.com/cultfilmsuk/p...77521798926357

[Geoff D]

Oh yeah, he hates it. I can't say that I agree.

[mysticwaterfall]

Originally Posted by hype88

Exact movie I used to shut a neighbor up real quick when he told me the difference was just in my head because of how much I spent on the tv and wanted to believe it. 4-5 months later he asked me what exact model I had because he was looking to replace the living room tv lol

Obviously there are standout HDR releases just like there were/are BluRay releases.. I have no intentions of not buying BluRay anymore, I am just not going to buy most that I feel a 4k release is coming around the corner. HDR and Dolby Vision are still somewhat new as well and will only improve over time imo.

To say HDR is just a gimmick is pretty ridiculous at this point if you have watched some of the better releases. I was skeptical in the very beginning as well but it's clearly superior when done right. Sound wise, the new Dolby Atmos tracks on some 4k releases are also a big improvement and something I hope to see on many future Horror 4k releases.

Indeed. My wife is one of those people who would just watch DVDs or streaming all day and rolls her eyes when I talk about things being better on other formats. So when we got the c6 she was skeptical until we watched Planet Earth together where she was amazed by how vibrant the color was.

Plus, I hate to break it to "film purists" but the home release has always been processed in some way, unless you're watching the original film and or 10TB file.

[billy35]

Originally Posted by Geoff D

A 10-bit 2K master of a 2hr movie will clock in at 2TB. A 10-bit 4K master will be 8TB. Lowry use a special process to analyse and enhance their transfers which is why it needs so much bandwidth to process, but the final master would be the same size as those just mentioned.

At best we're looking at maybe 80 or 90GB of 4K video on a 100GB disc, leaving room for audio, menus and whatnot. 8TB into 90GB doesn't take a genius to work out, these discs are MASSIVELY compressed from the original so when people talk about it being a virtual copy of the negative or whatever then I wouldn't take it so literally. What they are saying is how fantastic it looks.

Thanks Geoff! So, now I wonder how much is lost with all this massive compression.. And yet, it still looks amazing. Am I correct to assume that it has more to do with the tv size being much smaller than that of a theatre screen/also the way our eyes notice these details/viewing angle/distance? I remember when me and my friend were listening to flac and mp3 320 kbps files. We rarely could figure out which was the lossless one and which one was lossy. They both sounded absolutely great to our ears on a particular sound system. Although obviously, one file was inferior and compressed when compared to the other one.

I bet those 8TB discs would look like laserdisc. Honey I Blew Up the Kid

[Moonlight Shadow]

As long as experts like Robert Harris and Torsten Kaiser say that the use of HDR makes a transfer a less accurate representation of the original film source I'll only buy HDR UHDs of new shot-on-digital movies.
I'll make exceptions when the Blu-ray looks horrible compared to the UHD (e.g. "Predator").

[Geoff D]

Originally Posted by billy35

Thanks Geoff! So, now I wonder how much is lost with all this massive compression.. And yet, it still looks amazing. Am I correct to assume that it has more to do with the tv size being much smaller than that of a theatre screen/also the way our eyes notice these details/viewing angle/distance? I remember when me and my friend were listening to flac and mp3 320 kbps files. We rarely could figure out which was the lossless one and which one was lossy. They both sounded absolutely great to our ears on a particular sound system. Although obviously, one file was inferior and compressed when compared to the other one.

I bet those 8TB discs would look like laserdisc. Honey I Blew Up the Kid

It's not to do with TV sizes, it's to do with being able to transport 2TB/8TB of data (which is usually stored on high-density tape like LTO, not disc) into people's homes, as well as the age old concerns of Hollywood not wanting to give people 1:1 copies of movies.

For as long as movies have been put onto 5" shiny disc they have been heavily compressed from the source files using what are called interframe codecs. These compress one into the other by preserving one frame in its entirety and storing however many that follow it as difference data, i.e. only the crucial parts that differ from the reference frame are stored, not the whole frames themselves. The player is then able to reconstruct the full amount of frames upon playback of the disc by analysing the data next to the reference frame, and it does all this in the blink of an eye. Same goes for BD, DVD etc.

Colour resolution is also greatly reduced from that of the source masters, the "4:2:0" that some people may have heard of. This method of chroma subsampling essentially reduces the colour information into a quarter of the overall resolution, so for 3840x2160 you get 1920x1080 effective chroma rez put onto disc which is then upsampled by the player/TV back into full rez chroma.

These processes are not lossless and so something has to give, possibly losing detail in terms of spatial, temporal and chroma resolution, but for the most part unless you literally had the studio master playing back on a $30K monitor side-by-side with the consumer disc you'd be none the wiser as to what you're missing, and even then the differences might be very hard to spot.

BTW even the theatrical DCPs (Digital Cinema Packages) that are used to distribute movies to cinemas aren't 1:1 copies either, the video is compressed using an intraframe codec called JPEG2000 which stores each frame in its entirety, meaning that DCPs often run upwards of 100GB and usually hit 200GB or more. But these DCPs have a higher bit-depth and wider colour gamut than regular 8-bit 709 Blu-ray, with no chroma subsampling either, whereas the 10/12-bit depth and P3 (inside 2020) colour space of UHD disc ensures a closer representation of the source files (and beyond, thanks to HDR). UHD's chroma still uses that 4:2:0 subsampling but look at this way: it's still 4x the colour resolution of Blu-ray and that alone can make a visible difference.

[mysticwaterfall]

Originally Posted by Moonlight Shadow

As long as experts like Robert Harris and Torsten Kaiser say that the use of HDR makes a transfer a less accurate representation of the original film source I'll only buy HDR UHDs of new shot-on-digital movies.
I'll make exceptions when the Blu-ray looks horrible compared to the UHD (e.g. "Predator").

It's your choice, but you would be denying yourself some amazing releases like the 90's Mummy then.

[Charlie_C]

Originally Posted by mysticwaterfall

It's your choice, but you would be denying yourself some amazing releases like the 90's Mummy then.

Yup, it's a crazy thing to say. Pretty much all of my favourite 4K releases have come from OCN scans. They are what this format was made for IMO.

[smithb]

Originally Posted by Vilya

Mr. Harris has posted a number of reviews where he has praised the 4K HDR releases of both recent and older films.

Look at his reviews for Halloween and Die Hard; he said the the latter was "perfect in every regard" with "Full film resolution, with requisite grain, perfect color, deep rich blacks, and stable as a rock" and that the former was "Absolutely gorgeous, with beautifully rendered color, great shadow detail, and luscious moving grain."

Are these the words of someone who dislikes what HDR can do?

I believe that the OP has an agenda as he conveniently omits the many instances where Mr. Harris has praised 4K HDR releases.

Originally Posted by Geoff D

Most 1080p SDR 709 iterations "don't truly represent the original print" either. Each OETF/EOTF for video is a compromise intended to turn film light into electrical signals and then back again, and the old gamma system (designed around the CRT TVs of yore) has served us well but HDR is capable of providing so much more of the original expression, albeit with the caveat of potentially showing us everything that was intended and well beyond.

Even so, what does the "original print" matter to some filmmakers? Ridley Scott and Michael Mann revise the look of their films every time they go up for a new transfer and plenty of others indulge in revisionism of one form or another (fixing of the falling licence plate in Goodfellas, removal of several goofs and imperfections in Aliens, Titanic and T2). Not saying two wrongs make a right, but I am saying that the goalposts get moved an awful lot these days.

Reading through the thread, these are two posts that really stood out to me.

First, having read several of his reviews on UHD releases, Mr. Harris is definitely not against HDR. I think many of the quotes presented are nothing more than a fear of HDR being over used, like DNR, and thus (in this case) his statements are ultra conservative. Especially, when it comes to films where HDR was obviously not a consideration in post processing. As someone else insinuated, stringing several quotes together to suit a purpose, is not always a fair assessment of an individuals true belief.

As Geoff stated, we have revisionism across releases when even the original creators are involved, so the expectation that there won't be the same when new individuals take the reins of older films is very unlikely, so one might as well go in expecting it. In some cases, it may be subtle and others not. In the end, as we do now, you either buy into the changes (literally) or you don't. It's a choice.

[Geoff D]

Originally Posted by Moonlight Shadow

As long as experts like Robert Harris and Torsten Kaiser say that the use of HDR makes a transfer a less accurate representation of the original film source I'll only buy HDR UHDs of new shot-on-digital movies.
I'll make exceptions when the Blu-ray looks horrible compared to the UHD (e.g. "Predator").

It's funny how very respected restoration houses like Warners' MPI are able to work up SDR and HDR versions of a film just fine though, whereas Torsten bangs on about how transplanting SDR over into HDR doesn't work - well of course it bloody well wouldn't! The HDR has to be graded from scratch in that colour space and in that EOTF, and if so desired can be made to look virtually identical to the SDR for colour. Just look at the images of American Psycho in 4K, freshly remastered from the 35mm original and yet you can surely see how little the colour differs from the previous transfer in terms of making giant swerves in creative intent.

At the end of day it's ALWAYS been about the taste of the people who are twiddling the knobs and HDR is no different. Sheehs, even SDR 709 iterations of several films can and do look wildly different from one transfer to the next for that same reason. Look at Suspiria! Two SDR 709 iterations on Blu, supposedly remastered from the same scan at source, and using the same reference materials, one supervised by the DP and one supervised by TLE and yet they look drastically different, with each side insisting that theirs is the most "accurate" version. Them targets keep on moving...

[smithb]

Originally Posted by Moonlight Shadow

As long as experts like Robert Harris and Torsten Kaiser say that the use of HDR makes a transfer a less accurate representation of the original film source I'll only buy HDR UHDs of new shot-on-digital movies.
I'll make exceptions when the Blu-ray looks horrible compared to the UHD (e.g. "Predator").

This reminds of the discussion of whether the strings holding the spaceships in the original "War of the Worlds" should be removed or maintained in a future HD release. The purist will say leave them in because they have always been there and are part of the film. Revisionist say, if the creator had a convenient method of removing them back then, wouldn't they have?

I see HDR the same way for older films. If the ability was there to utilize it in post processing back then, would they have to further change the look? I would guess "yes", since most will take advantage of any tools available. As to how extensive they would use it on a film by film basis, no one knows.

I agree with others, I'm not a purist to that extent to totally ignore HDR use on older films. Like anything else, sample the results, if you like it buy it, if not don't. I'd suggest taking it on a release by release basis, not on whether HDR was available when the film was made or not.

[Moonlight Shadow]

Originally Posted by mysticwaterfall

It's your choice, but you would be denying yourself some amazing releases like the 90's Mummy then.

I'd get the Mummy UHD if I would like the movie more.

[Geoff D]

Originally Posted by smithb

This reminds of the discussion of whether the strings holding the spaceships in the original "War of the Worlds" should be removed or maintained in a future HD release. The purist will say leave them in because they have always been there and are part of the film. Revisionist say, if the creator had a convenient method of removing them back then, wouldn't they have?

I see HDR the same way for older films. If the ability was there to utilize it in post processing back then, would they have to further change the look? I would guess "yes", since most will take advantage of any tools available. As to how extensive they would use it on a film by film basis, no one knows.

I agree with others, I'm not a purist to that extent to totally ignore HDR use on older films. Like anything else, sample the results, if you like it buy it, if not don't. I'd suggest taking it on a release by release basis, not on whether HDR was available when the film was made or not.

Yeah, I mean I'm not sold on that kind of "would they have wanted HDR at the time" second-guessing (which could just as easily be applied to colour if talking about much older movies) in order to justify my stance on it, I tend to just go with the flow now and take them as they come.

SDR 709 is hamstrung by certain things, at least when talking about the compressed 8-bit consumer iteration (unlike, say, the 10-bit or higher uncompressed masters with full chroma that Torsten et al will be used to seeing), and so that's why I prefer UHD Blu-ray like I do, it's got the scope to truly do justice to the originals at last. It then also brings with it that much larger box of crayons and it's up to each person to decide how comfortable they are with however many more crayons over and above the original intent are being used, not that we're going to know anyway without an unfaded answer print or release print being projected side by side with it. Still, as the saying goes: "I'd rather have it and not need it, than need it and not have it".

[xbs2034]

Originally Posted by Moonlight Shadow

Restoration expert Torsten Kaiser is also opposed to the use of HDR for older movies. His very detailed explanation can be found here:

https://m.facebook.com/cultfilmsuk/p...77521798926357

I can understand that, as it can change the intended look (not that other modern technologies can't also change the picture and sound in ways the filmmakers never could have imagined) which is why I always prefer if the director or cinematographer oversees an HDR grade on an older movie, of course that isn't always possible particularly the older movies get.

As for the quality of HDR, I agree it is the big selling point of the format. Sure the 4K resolution looks nice, but I don't think it is usually a huge increase and I've never felt a great HD transfer lacks in detail and image quality, but it's in the HDR where I can find jaw dropping differences. And of course it is easier on new releases which very much take it into account during production, but also on older films (just was watching The Lost World a few days ago, and I feel the HDR makes a huge difference in that movie with its darker cinematography and vibrant colors in the brighter scenes).

[Moonlight Shadow]

Originally Posted by Charlie_C

Yup, it's a crazy thing to say. Pretty much all of my favourite 4K releases have come from OCN scans. They are what this format was made for IMO.

Since some renowned experts share my opinion it can't be so crazy, can it?

Look, I'm not trying to preach or convince anybody.
If you like old movies to have a shiny HDR look you can buy them all again on UHD. I have no problem with that.

I prefer to watch movies to look like I remember them from the cinema so I prefer a perfect Blu-ray to a UHD.
I'm also one of those guys who always watches old movies with their original mono mix. Yeah, "crazy", I know.

I'll get the occasional UHD for an old movie if the Blu-ray transfer looks very dated and IF I like the movie enough to spend more money on it.

[HeavyHitter]

Originally Posted by Ruined

Too bad studios dont offer both, projector uses would likely greatly appreciate a 4k sdr rec2020 disc.

It would certainly not be financially feasible to offer and SDR 2020 version. However, good tone mapping solutions (especially something like the Panasonic 820) take care of this based on my experience. I have no desire or need for an SDR 2020 version based on what I am now seeing which is probably something like "SDR+" or "HDR lite". It's still more highlight range than SDR BD.

[Ruined]

Originally Posted by HeavyHitter

It would certainly not be financially feasible to offer and SDR 2020 version. However, good tone mapping solutions (especially something like the Panasonic 820) take care of this based on my experience. I have no desire or need for an SDR 2020 version based on what I am now seeing which is probably something like "SDR+" or "HDR lite". It's still more highlight range than SDR BD.

Tone mapping helps make the format workable for sure, but given the dynamic nature of tone mapping that widely varies from device to device - how much of the final product on your screen is the filmmakers intent vs Panasonics?

Thats really the crux of the issue, we've moved on from reproducing exactly what is on the disc to reproducing an interpretation of what is on the disc depending on our settings preferences and electronics capabilities; on top of this, it may take a decade to get projectors to a 1000nit equivalent in anything remotely approaching a reasonable price. Basixally no more true accuracy of visual reproduction of disc content, instead only getting what looks "good" on my display/player. Or, must settle for a very small screen that doesn't really provide a truly immersive cinematic experience. For a purist I could see why this is a highly undesirable outcome.

Of course having two 4k versions (SDR and HDR) could resolve this but as you stated it may be financially unfeasible for most films.

[CarlosMeat]

Originally Posted by Ruined

Tone mapping helps make the format workable for sure, but given the dynamic nature of tone mapping that widely varies from device to device - how much of the final product on your screen is the filmmakers intent vs Panasonics?

Thats really the crux of the issue, we've moved on from reproducing exactly what is on the disc to reproducing an interpretation of what is on the disc depending on our settings preferences and electronics capabilities. Basically true accuracy of visual reproduction vs. what looks "good" on my display/player. For a purist I could see why this is a highly undesirable outcome.

Of course having two 4k versions (SDR and HDR) could resolve this but as you stated it may be financially unfeasible for most films.

True ,yet the only way to make it work based the capabilities of the display technologies.

[Charlie_C]

Originally Posted by Moonlight Shadow

Since some renowned experts share my opinion it can't be so crazy, can it?

Look, I'm not trying to preach or convince anybody.
]If you like old movies to have a shiny HDR look you can buy them all again on UHD. I have no problem with that.

I prefer to watch movies to look like I remember them from the cinema so I prefer a perfect Blu-ray to a UHD.
I'm also one of those guys who always watches old movies with their original mono mix. Yeah, "crazy", I know.

I'll get the occasional UHD for an old movie if the Blu-ray transfer looks very dated and IF I like the movie enough to spend more money on it.

Sure man, it's all good but my comment was aimed at the fact that 4K UHD is as close as we have come to replicating 35mm film projection in our living rooms. WCG and HDR literally make this possible so saying that you only buy new digitally shot films on the format seems like you're shooting yourself in the foot a bit. You will miss out on a lot of great releases especially when you "prefer to watch movies to look like I remember them from the cinema". Unless you watched blu-ray discs in the cinema somehow that doesn't really make much sense.

Each to their own though.

And original mono is mandatory imo...