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Dave Blair

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Very broadly speaking...

“Mastering” is the process by which you end up with a completed copy of the content that has the visual and audio elements finished the way the content creators wants. With older content shot on film, that involves scanning the film, performing color correction, image cleanup and stabilization, and audio cleanup. With newer content that originated digitally, its performing color correction and audio adjusting to make sure it looks and sounds as it’s supposed to. The idea is that when this process is over, you have a master copy that can be the basis for all future uses, whether that’s for movie theaters to show, cable companies to play on TV, streaming services to stream, home video labels to put on disc, etc.

“Authoring” is the specific process of taking that completed master and converting it to a format that plays on the disc and conforms to the standards of that disc type, while still retaining the properties that the content creators have approved. For example, a finished master copy of a movie might take up hundreds of gigabytes of space, or even terabytes. A Blu-ray disc, by comparison, can only hold up to 50 gigabytes of space. Authoring is the process by which that data is compressed to fit onto the disc.
Thanks. Where then does HDR come into play? Are 2 masters created? It would seem risky to have HDR baked into the master only to have to remove it if and when improved technology arrives and I know it will.
 

titch

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Thanks. Where then does HDR come into play? Are 2 masters created? It would seem risky to have HDR baked into the master only to have to remove it if and when improved technology arrives and I know it will.
Robert Harris has previously provided a good explanation of where HDR is applied:

"...generally NOT a part of the design of a film, with most HDR entering the picture, no pun intended, during post.

"Wouldn't look neat if those flames were Really bright orange..."

It's added the same way that 3D is added in post, to the majority of 3D productions.

It has no relevance to production photography.

It should not be included as a function for classic films, unless the filmmakers have a desire to re-visit, and create a new version, a re-imagining".


Judging by the information provided on the Second Sight Dawn Of The Dead booklet, it would appear to my eyes that HDR is baked into the master, after scanning the elements at 4K, by Lauren Quinn and Chris Frankland at restoration company Final Frame. The masters were then sent to David Mackenzie at Fidelity in Motion for mastering/authoring for the disc. I'm sure insiders would be able to confirm where the HDR is applied. In this case, it seems as though both companies worked closely with each other, which is probably the key to producing superb results.

But whoever is done it on the Second Sight disc, has done it delicately. Like Robert Harris says, "a whiff of vermouth waved over a martini".

I wish all publishers could provide such transparent and clear information regarding the people and companies involved at each stage. If the upcoming 4K UHD disc of My Fair Lady turns out to look vastly different from the beautifully restored blu ray in 2015, I would like to know where that happened and who was responsible. I'm sure most people purchasing don't care about such details but I've noticed that some people and companies constantly produce beautiful discs, while some companies have a very variable output. It's very obvious that buying a "restored" or "remastered" 4K UHD disc in no way guarantees that you will see a quality picture projected onto a screen.

And for some people, the only thing that seems to matter for them, is that there is HDR slathered all over the picture (see the The Good. The Bad and The Ugly (1966) (4K UHD) thread).
IMG_3262_edited-1.jpg IMG_3264.jpg
 

Dave Blair

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Thank you for the explanation and the work that went into it. I would like more transparency as well, and iNFB on who sighed off on the project
 

Robert Harris

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Robert Harris has previously provided a good explanation of where HDR is applied:

"...generally NOT a part of the design of a film, with most HDR entering the picture, no pun intended, during post.

"Wouldn't look neat if those flames were Really bright orange..."

It's added the same way that 3D is added in post, to the majority of 3D productions.

It has no relevance to production photography.

It should not be included as a function for classic films, unless the filmmakers have a desire to re-visit, and create a new version, a re-imagining".


Judging by the information provided on the Second Sight Dawn Of The Dead booklet, it would appear to my eyes that HDR is baked into the master, after scanning the elements at 4K, by Lauren Quinn and Chris Frankland at restoration company Final Frame. The masters were then sent to David Mackenzie at Fidelity in Motion for mastering/authoring for the disc. I'm sure insiders would be able to confirm where the HDR is applied. In this case, it seems as though both companies worked closely with each other, which is probably the key to producing superb results.

But whoever is done it on the Second Sight disc, has done it delicately. Like Robert Harris says, "a whiff of vermouth waved over a martini".

I wish all publishers could provide such transparent and clear information regarding the people and companies involved at each stage. If the upcoming 4K UHD disc of My Fair Lady turns out to look vastly different from the beautifully restored blu ray in 2015, I would like to know where that happened and who was responsible. I'm sure most people purchasing don't care about such details but I've noticed that some people and companies constantly produce beautiful discs, while some companies have a very variable output. It's very obvious that buying a "restored" or "remastered" 4K UHD disc in no way guarantees that you will see a quality picture projected onto a screen.

And for some people, the only thing that seems to matter for them, is that there is HDR slathered all over the picture (see the The Good. The Bad and The Ugly (1966) (4K UHD) thread).
View attachment 87529 View attachment 87530
In regard to MFL, the new streaming version currently fails in projection. I would give it some quality time via OLED, where it also appears problematic, but it’s streaming.

If it appears the same via 4k physical media, it will fail. No need to add HDR or Dolby Vision.
 

Ray H

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Very broadly speaking...

“Mastering” is the process by which you end up with a completed copy of the content that has the visual and audio elements finished the way the content creators wants. With older content shot on film, that involves scanning the film, performing color correction, image cleanup and stabilization, and audio cleanup. With newer content that originated digitally, its performing color correction and audio adjusting to make sure it looks and sounds as it’s supposed to. The idea is that when this process is over, you have a master copy that can be the basis for all future uses, whether that’s for movie theaters to show, cable companies to play on TV, streaming services to stream, home video labels to put on disc, etc.

“Authoring” is the specific process of taking that completed master and converting it to a format that plays on the disc and conforms to the standards of that disc type, while still retaining the properties that the content creators have approved. For example, a finished master copy of a movie might take up hundreds of gigabytes of space, or even terabytes. A Blu-ray disc, by comparison, can only hold up to 50 gigabytes of space. Authoring is the process by which that data is compressed to fit onto the disc.
It seems companies like Criterion and Arrow use the term "restoration" to refer to the scanning, clean-up, and making of a new video master, "mastering" to refer to the encoding/compression of said master to a format/size compatible to Blu-ray/4K UHD disc, and "authoring" to refer to the act of compiling the video clips, audio tracks, subtitles, and menus into the final Blu-ray files for replication.
 

titch

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It seems companies like Criterion and Arrow use the term "restoration" to refer to the scanning, clean-up, and making of a new video master, "mastering" to refer to the encoding/compression of said master to a format/size compatible to Blu-ray/4K UHD disc, and "authoring" to refer to the act of compiling the video clips, audio tracks, subtitles, and menus into the final Blu-ray files for replication.
Yes - all these different terms are used for different processes by various companies and publishers, so it is sometimes difficult to know what they are talking about.

I have gathered, over the past years, from the valuable input from insiders on this forum, that the term "restoration" is used rather indiscriminately by publishers. A faded and damaged negative or print, which is returned to a condition similar or superior to when it was first released, is a "restoration". A new 4K scan of a negative, which hasn't needed anything other than the scan before the mastering for video compression, is not a "restoration". After scanning, the video and audio are treated, so as the results can be compressed for streaming, or for putting onto a little silver disc for home use. The terms authoring and mastering sometimes have been used interchangeably. I would just like transparent information from the publishers.

On StudioCanal's 4K UHD of The Elephant Man, there is scant information provided. Furthermore, there is no mention about the people responsible for the restoration of the negative at L'Immagine Ritrovata (Bologna and Paris) and colour correction at FotoKem. And absolutely no mention at all that the mastering and subsequent authoring for the 4K UHD, blu-ray and DVD was done by Fidelity In Motion. You have to go to Fidelity In Motion's website to find that out.
IMG_3269.jpg
On Criterion's blu ray of The Elephant Man, there is more detail - the scans of the negative were done by Silver Salt Restoration before restoration at L'Immagine Ritrovata in Bologna (no mention of Paris). George Koran at FotoKem is credited. Disc mastering is done by Pixelogic Media.
IMG_3272.jpg IMG_3271.jpg

In this case, is the superior image in the StudioCanal discs (to my eyes, et least) due to the different mastering efforts by Fidelity in Motion and Pixelogic Media? The discs are both produced from the same "restoration" scan and colouring/grading.

Crash is a similar case.On the Turbine Media 4K UHD disc, zero information about the scan, mastering and authoring, apart from the involvement of director David Cronenberg and DP Peter Suschitzsky. I haven't got the deluxe version - maybe there was more information in the booklet? No information before the film, or after the end credits either.

IMG_3273.jpg

Arrow Video provide much information about the "restoration" and have used Fidelity in Motion for the disc mastering. It is quite apparent that HDR is baked into the scanned master, before mastering for the disc.
IMG_3274.jpg IMG_3275.jpg
Criterion also provide information about the restoration (although the people involved are not credited) and have used Pixelogic Media for the disc mastering.They will most likely have used a scanned master without HDR baked in, since they didn't go for a 4K UHD.

IMG_3276.jpg
To my eyes, the picture projected looks very similar on both 4K discs, and the 4K image beats Criterion's blu-ray.

Arrow Video, Second Sight and Criterion provide good information about the people and companies involved at each stage of producing a video disc.
 

Robert Harris

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Much of this information references post-production functionality. Not restoration.

But that’s one persons opinion.

If a complete original negative can be scanned, colored, et al, that references a project not in need of restoration.
 

Worth

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Thanks. Where then does HDR come into play? Are 2 masters created? It would seem risky to have HDR baked into the master only to have to remove it if and when improved technology arrives and I know it will.
Typically, two separate masters are created. Or more like one-and-a-half. The majority of effort is spent on the SDR, then the colours and range are tweaked for the HDR version.
 

Bartman

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I believe the real reason why restoration, scanning and authoring info is generally not provided on the exterior case is, it provides the buyer with information about whether to buy this latest incarnation or not, that is, it is bad for sales versus the impulse buy. If the info is provided in (the back of) the booklet, or not at all, the uninformed buyer is unlikely to search it out and return the disc. The fact that the product has been opened is generally a deterrant to a return, too.
 
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Stephen_J_H

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Much of this information references post-production functionality. Not restoration.

But that’s one persons opinion.

If a complete original negative can be scanned, colored, et al, that references a project not in need of restoration.
Agreed. I am reminded of the work you posted about on The Godfather trilogy, in which you showed damaged frames, severe scratches and the like, not to mention the work on all your other projects. I appreciate that Criterion usually puts harvest details under a heading called "About the Transfer" rather than "About the Restoration."
Typically, two separate masters are created. Or more like one-and-a-half. The majority of effort is spent on the SDR, then the colours and range are tweaked for the HDR version.
This is where it gets interesting. Someone posted a video recently featuring Grover Crisp, where he talked about using HDR as a restoration tool to pull out detail and contrast not ordinarily visible in elements further down the chain than an OCN. If this is in fact possible, it would be significant to restoration. RAH, can you comment?
 

titch

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I believe the real reason why restoration, scanning and authoring info is generally not provided on the exterior case is, it provides the buyer with information about whether to buy this latest incarnation or not, that is, it is bad for sales versus the impulse buy. If the info is provided in (the back of) the booklet, or not at all, the uninformed buyer is unlikely to search it out and return the disc. The fact that the product has been opened is generally a deterrant to a return, too.
That could well be a valid reason. I've certainly noticed a few names that keep appearing with quality product. If I see Fidelity in Motion has mastered the disc, I am quite confident that the result will look great projected. Arrow Video have a stellar track record so far. I've decided to stop buying German, French and Italian 4K UHD discs, as the results are too inconsistent and they generally don't provide information about the people and companies responsible. These titles are seldom reviewed by websites, and it isn't always easy to judge the screen captures on Caps-a-holic. The American companies producing 4K discs aren't much better at providing information on scanning and mastering, but at least they get reviewed fairly widely, so that I can make my mind up about whether I want to purchase them, or not. The one US company producing 4K UHD titles that don't always look good on my projection set-up, is Warner Bros. For some reason, the picture appears darker on quite a few titles. They are probably mastered to look their best on an OLED panel display.
 

Robert Harris

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I've asked Mr. Mackenzie if he'd be willing to field some questions from HTF members, and he has agreed.

Please be aware that he cannot discuss upcoming projects or obviously internal facts.

If you keep your questions to the technical, this could become an interesting and lively thread.

RAH
 

Stephen_J_H

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I've asked Mr. Mackenzie if he'd be willing to field some questions from HTF members, and he has agreed.

Please be aware that he cannot discuss upcoming projects or obviously internal facts.

If you keep your questions to the technical, this could become an interesting and lively thread.

RAH
Looking forward to it. I have many questions.
 

dmac

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Hi everyone,

titch said:
Judging by the information provided on the Second Sight Dawn Of The Dead booklet, it would appear to my eyes that HDR is baked into the master, after scanning the elements at 4K, by Lauren Quinn and Chris Frankland at restoration company Final Frame. The masters were then sent to David Mackenzie at Fidelity in Motion for mastering/authoring for the disc. I'm sure insiders would be able to confirm where the HDR is applied. In this case, it seems as though both companies worked closely with each other, which is probably the key to producing superb results.

We usually get separate SDR and HDR masters delivered. Further up the chain, the colorist might work first in SDR and then do an HDR pass after that (I'd need to clarify). Setting color and brightness etc. are the job of the colorist, and that goes for both SDR and HDR. On the compression side, my job is to make sure that those levels don't shift around. The HDR isn't added in compression and authoring (any more than color is), but those processes obviously need to be set up correctly to carry any necessary metadata that might be useful to the display.

One of the advantages of Dolby Vision (although it wasn't used on Dawn) that might not be apparent from the outside is that it makes a single master possible. So you get delivered pixel data that conforms to Rec.2020+HDR (or P3+HDR) along with an XML file output by the grading system that describes exactly how the content should be gamut and tone mapped down to Rec.709+SDR, since the colorist in a Dolby Vision setup will have been monitoring how the image looks on various different displays (high brightness HDR, low brightness HDR, SDR and so on). Software can read that and then generate the SDR version from the HDR+metadata. But in practice, the people supplying the masters usually just deliver both.

Dawn was an unusual case in that I actually did some restoration work on it, specifically near the ends of one of the reels that had a lot of instability and needed manual rotoscoping.

But our specific area of work is in maintaining image quality in compressed media, not in scanning and restoration or that side of mastering. (Technically, making replication data for Blu-ray Disc manufacturing is a form of mastering, but not in the way it was put forward in this thread).

The actual compression/encoding (and less excitingly, authoring) stuff doesn't get talked about as much, probably because it's not as easily understood. I think the average person understands what film restoration is, data reduction and formatting, not so much. I think there's an unspoken idea that it's just something that happens to the data to get it onto the disc (or into the file), but the decisions made during this process can have a critical effect on the end result, especially when there's film grain or other important textures involved. There's so much data being approximated that it couldn't not.
 

B-ROLL

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Thank you so much for providing this opportunity for us to ask questions?

Back when I was studying and briefly worked in television broadcasting every production house, including local stations and networks had Standard Operating Procedures for tapes for broadcast. This was typically 30 seconds of "Slate" giving production information length, title, advertiser in the case of commercials etc. This was then followed by two minutes of color bars including a 1,000 cycle tone at 100db/Volume Units for adjustments to video and audio. This would either be followed by an Academy Leader or 10 seconds of TV black and either the program or promos/spots (which would usually be indicated on the slate or in a cue sheet enclosed with the tape).

I've noticed on several discs (none that you have done that I am aware) that there is a significant difference between the menu audio and the program audio. Often volume is 40-60 % below that of the menu or company logos before the program begins.

My question is when you receive the SDR and HDR masters is there some similar sort of audio level indicator that could be adjusted or would the entity that does the mastering be flying blind so-to-speak?

Thank you again for your courtesy.
 

titch

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Hi everyone,



We usually get separate SDR and HDR masters delivered. Further up the chain, the colorist might work first in SDR and then do an HDR pass after that (I'd need to clarify). Setting color and brightness etc. are the job of the colorist, and that goes for both SDR and HDR. On the compression side, my job is to make sure that those levels don't shift around. The HDR isn't added in compression and authoring (any more than color is), but those processes obviously need to be set up correctly to carry any necessary metadata that might be useful to the display.

One of the advantages of Dolby Vision (although it wasn't used on Dawn) that might not be apparent from the outside is that it makes a single master possible. So you get delivered pixel data that conforms to Rec.2020+HDR (or P3+HDR) along with an XML file output by the grading system that describes exactly how the content should be gamut and tone mapped down to Rec.709+SDR, since the colorist in a Dolby Vision setup will have been monitoring how the image looks on various different displays (high brightness HDR, low brightness HDR, SDR and so on). Software can read that and then generate the SDR version from the HDR+metadata. But in practice, the people supplying the masters usually just deliver both.

Dawn was an unusual case in that I actually did some restoration work on it, specifically near the ends of one of the reels that had a lot of instability and needed manual rotoscoping.

But our specific area of work is in maintaining image quality in compressed media, not in scanning and restoration or that side of mastering. (Technically, making replication data for Blu-ray Disc manufacturing is a form of mastering, but not in the way it was put forward in this thread).

The actual compression/encoding (and less excitingly, authoring) stuff doesn't get talked about as much, probably because it's not as easily understood. I think the average person understands what film restoration is, data reduction and formatting, not so much. I think there's an unspoken idea that it's just something that happens to the data to get it onto the disc (or into the file), but the decisions made during this process can have a critical effect on the end result, especially when there's film grain or other important textures involved. There's so much data being approximated that it couldn't not.
This is really illuminating! And very exciting to hear from one of the people who has been responsible for the very best home video discs during the last few years. For myself, who projects films at home, instead of using a flat panel OLED monitor, anything produced by Fidelity in Motion looks fantastic screened at 130 inches via a cheap 4K projector! As you say, the average person doesn't know much about the processes that happen in bringing a restored scan onto a consumer version of a disc. I certainly have a steep learning curve, after 30 years of collecting consumer home video formats. And it all gets even more confusing for us amateurs when the original scan is called "remastered" and then there is disc "mastering" before disc "authoring". I have purchased European and American blu-rays and 4k UHDs and there quite often a noticeable difference in the quality between the various publishing companies' versions when I project at home. Information about the people and companies involved at these various stages is usually scant. However, some companies are to be commended about the information they do provide - Arrow Video and Second Sight have been more comprehensive than most.

I have two questions for you:
1) I was comparing the Oldboy Arrow Video 4K UHD with the German Capelight 4K UHD and Arrow Video blu-ray, yesterday. The picture is pretty grainy and contrasty in parts, but both Arrow Video discs looked superior than the Capelight Pictures projected onto a 130 inch screen. The bitrate was much higher on the Arrow Video 4K. Since you were responsible for the mastering of this disc (which looked like it was based on the original master delivered to both companies), does a higher bitrate at, say 80 Mbps necessarily give advantages over 40 Mbps in this format?

IMG_3283.jpg IMG_3282.jpg
2) As part of the disc mastering, did I understand you correctly, when you wrote that both colour and compression are stages in this process? And that the master delivered from the studio contains SDR and HDR data "baked in"? We have been discussing titles that have not been done by your company. I have noticed on some titles, that the picture colour and contrast differs tremendously between the blu-ray and 4K disc versions, made from the same master, e.g. Unforgiven. I was wondering where in the process this might have occurred and presumed it was in the later stages of disc mastering.

As Robert Harris writes, a restored film master can be wrecked by the injudicious application of Dolby Vision and HDR. The 2020 4K streaming version of My Fair Lady does not look as good projected, as the 2015 blu ray. We are speculating what the forthcoming 4K UHD will look like, whether mastering for disc will salvage the image when projected.
 

dmac

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My question is when you receive the SDR and HDR masters is there some similar sort of audio level indicator that could be adjusted or would the entity that does the mastering be flying blind so-to-speak?
The masters typically contain PCM audio, which needs to get extracted before it gets encoded (or just passed through as is if it's going on the disc as PCM). You can view that waveform with any standard software. If it seems especially quiet then we'll adjust it upwards (but never in a way that would cause anything to clip). Having audio levels across elements be consistent is something usually taken care of as part of the authoring process.

For Titch's questions: #1: For a film like this, yes, absolutely. OLDBOY has a lot of very nice, natural, sharp grain (on the original camera negative portions, that is). It needs the lowest level of quantization possible. If too many of the high frequency (sharpest, finest details) components get dropped during the compression process to achieve a lower bitrate, the end result will look smoothed over and gloopy. Arrow is excellent at using UHD100 discs whenever we ask for them.

Even with that size of disc, my strategy is always to do a lot of noise reduction and compression on the bonus features, to make room on the disc for all the grain. This just makes sense becuase nobody really cares if a video interview isn't presented with its original video camera noise intact, but preserving the original grain is essential for a high quality presentation. So the bonus features use a tiny portion of the disc because they're very compressable with a lot of pre-optimization. CINEMA PARADISO is another example of this, if I recall correctly the feature is on there at CBR 95mbps. The bonus features had to be recompressed for the UHD BD because they were originally interlaced (UHD BD doesn't support interlaced formats), so we took the opportunity to redo them in HEVC and compress them further. More room for the film.

#2: We don't change the color or the brightness, or any other artistic decision, in compression, because it's the colorist's job.

Re "baked in", by definition, yes - whether it's SDR or HDR, we get delivered pixel data, in either an RGB or Y'CbCr format. That numerical data describes the color of each pixel. The only difference with HDR is that with the advanced HDR formats, you have additional metadata that syncs to the picture that ultimately gets carried in the compressed video that provides pointers to lower brightness displays on how to best present the video.

We have been discussing titles that have not been done by your company. I have noticed on some titles, that the picture colour and contrast differs tremendously between the blu-ray and 4K disc versions, made from the same master, e.g. Unforgiven.
They won't be made from the same master, but instead will have been made from separate SDR and HDR masters. And there's a lot that could look different between the SDR/Rec.709 version and an HDR/Rec.2020 version, and a lot the display could be doing to it to make it look different, if it didn't already. With SDR we could achieve totally accurate display, but HDR's use of tone mapping rewrites the rules somewhat, especially with projectors where the brightness is limited.
 
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B-ROLL

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The masters typically contain PCM audio, which needs to get extracted before it gets encoded (or just passed through as is if it's going on the disc as PCM). You can view that waveform with any standard software. If it seems especially quiet then we'll adjust it upwards (but never in a way that would cause anything to clip). Having audio levels across elements be consistent is something usually taken care of as part of the authoring process.

For Titch's questions: #1: For a film like this, yes, absolutely. OLDBOY has a lot of very nice, natural, sharp grain (on the original camera negative portions, that is). It needs the lowest level of quantization possible. If too many of the high frequency (sharpest, finest details) components get dropped during the compression process to achieve a lower bitrate, the end result will look smoothed over and gloopy. Arrow is excellent at using UHD100 discs whenever we ask for them.

Even with that size of disc, my strategy is always to do a lot of noise reduction and compression on the bonus features, to make room on the disc for all the grain. This just makes sense becuase nobody really minds if a video interview isn't presented with it's original video camera noise intact, but preserving the original grain is essential for a high quality presentation. So the bonus features use a tiny portion of the disc because they're very compressable with a lot of pre-optimization. CINEMA PARADISO is another example of this, if I recall correctly the feature is on there at CBR 95mbps. The bonus features had to be recompressed for the UHD BD because they were originally interlaced (UHD BD doesn't support interlaced formats), so we took the opportunity to redo them in HEVC and compress them further. More room for the film.

#2: We don't change the color or the brightness, or any other artistic decision, in compression, because it's the colorist's job.

Re "baked in", by definition, yes - whether it's SDR or HDR, we get delivered pixel data, in either an RGB or Y'CbCr format. That numerical data describes the color of each pixel. The only difference with HDR is that with the advanced HDR formats, you have additional metadata that syncs to the picture that ultimately gets carried in the compressed video that provides pointers to lower brightness displays on how to best present the video.


They won't be made from the same master, but instead will have been made from separate SDR and HDR masters. And there's a lot that could look different between the SDR/Rec.709 version and an HDR/Rec.2020 version, and a lot the display could be doing to it to make it look different, if it didn't already. With SDR we could achieve totally accurate display, but HDR's use of tone mapping rewrites the rules somewhat, especially with projectors where the brightness is limited.
Thank you once again for your responses - I look forward to seeing your work again when I watch Cinema Paradiso on 4K for the first time :).
 

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