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[Idea] SDR -> HDR "upconversion"
#11
Rec.2020 is a wide color gamut. THAT is a legitimate thing to extract in new transfers. It doesn't require that the studios monkey with anything. Movies are shot for DCI-P3, an even wider colorspace than Rec.2020.

HDR, on the other hand, is an expansion of white and black levels (luminance). It allows for brighter highlights and deeper shadows. Combined with Rec.2020 you have a larger color VOLUME, movies were NEVER shot with this in mind.

To assume that older movies were shot on film (or digital) without the people involved understanding things like lighting and the capabilities of their cameras, the film stock and movie theater projectors is pretty much an insult to every member of a movie's crew.

You could argue that they INTENDED it to look like what HDR discs look like now and the technology just wasn't there.
But that is the George Lucas Special Edition argument.
When HDR came out, some studios actually had to take filmmakers aside and give them a lesson in what the hell HDR is.

@Stamper, keyboards are in input device, not output. Not a good argument.

Btw, we used to have a Mitsubishi Laservue. It provided an enhanced colorspace before Rec.2020 was a thing. There was a picture mode that would extrapolate into that wider gamut. It was eye-popping at the time. I still believe enhancing colorspace is possible, but not dynamic range.
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#12
(2018-04-19, 07:28 AM)Doctor M Wrote: Movies are shot for DCI-P3, an even wider colorspace than Rec.2020.
Actually, DCI-P3 is in between Rec.2020 and Rec.709
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#13
So HDR IS just a gimmick.
I was almost sold on it recently though to be honest, there is an awful lot of fanfare around it.
I get having panels with a greater (real) contrast ratio, and the exciting thing about the recent 10bit panels (real) has been the increased/wider colour gammut.
It would of been nice if the home media delivery systems just gave us YCbCr 4:4:4 and a more lossless codec but I digress.....
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#14
Nah it's not a gimmick - the color space is just wider than it would necessarily need to be to represent most current movies. That doesn't negate the fact that Rec709 is way too small for the same task. It's not even possible to give a really accurate representation of a final 35mm film print in Rec709/SDR. You can notice that when you look at an actual film print or a slide image and then you look at the scanned one. While it may resemble it in most aspects there is a certainly brilliance that is lost.

In other words - it's better than it would need to be for most movies right now. But I think that's okay in the name of future proofing.

To be fair though - it's not usually fully filled up so the people in charge seem to be smart enough to show some restraint. If some of them do oversaturate and overcontrast current movies then that would be gimmicky in nature but the technology itself isn't.

Edit: I want to add another argument why it's not a gimmick. While most current movies may not have been made with the wide HDR colorspace in mind, there's an area that very well does profit from it, if it is used for that: Documentaries and anything trying to resemble the way things actually look in real life. Movies often use tricks to reduce the dynamic range of scenes to make them fit in the recording color space better. But real life shows an incredible variety of dynamics and Rec709 struggles *immensely* with portraying those. I'm really glad HDR is here to come closer to showing realistic real world representations. Imagine a scene of a dark cave shot against the bright sunlight. In the past you would be called crazy and incompetent for choosing such a shot as it would look horrendous in Rec709/Rec601. But now this may be an opportunity to get a really good looking and impressive shot. (as long as the framing etc. is good of course). Oh yeah and with that of course also comes the possibility of having much better looking memories for yourself once HDR consumer cameras become a thing. Just look at some of your personal casual recordings from the past ... notice all the constantly blown out highlights and crushed blacks ruining the image? No longer is that necessary!
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#15
Im confused again lol.

Is 'HDR' just a marketing term for 10bit rec2020?
I was under the impression it was until I kept hearing the positive talk about metadata and Dolby Vision, I initially thought was just there to guide panels that we're not up to snuff.
A proper 10biit panel that can cover full rec2020 should cover all the things you have mentioned and just be a standard in which to encode your deliverables to. The only need for metadata should be for the downscale to SDR or 'HDR' lite.

Im probably missing something major here though Smile
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#16
Of course typewriters are output. You output written pages.

Rec2020 goes with HDR. You can actually get more out of a film as long as you have the 10 or 12 bits or more files, with more accurate colors and contrast and luminance. It's not revisiting old films, is getting them closer to the film range.
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#17
I've been part of these discussions before, I have to say I don't think HDR is just a 10 bit image, reasoning, well HDR is an old Fujifilm tech, something they have spent the last 14ish years developing and licensing out to other manufacturers. Basically it was their way of getting film characteristic results from a sensor, so they analyzed all their film stock and made algorithms to copy them as best they could. There is no way Sony et al could be using their tech without permission, not unless they all wanted to get their asses sued from under them and HDR is theirs (Fujifilms), so logic alone suggests that HDR within UHD uses their algorithms, the how the colors are represented from "exposure".

Trying to match their results would be nigh on impossible, but using your techniques with a wider color gamut should still create gains and honestly 1080p HDR still makes more sense, why the UHD consortium silenced Panasonic when they said they were planning on releasing both 4K and 2K HDR, to the point where their first UHD player was compatible with both. 4K, the resolution, is the gimmick, not HDR.
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#18
As far as I understand it, Rec2020/Rec2100 are simply the official standards surrounding HDR image. Individual technologies like HDR10 or Dolby Vision may reference that standard.

I don't 100% understand the need for metadata either. Since the metadata contains display calibration data, my wild guess is that the person who does the editing/color grading makes the final encode so that it looks good on their display, and they include their display's metadata so that other displays/systems can approximate what it looked like on the original display it was graded on. Of course you could simply create a general standard into which it is converted, but then you would possibly introduce further rounding errors or whatever? I don't know, I'm probably full of shit lol.
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#19
HDR capturing techniques were to extend beyond the dynamic range of a given sensor that normally would have been limited to 8bit BT709. It was a term to explain anything beyond the limit of SDR. Capturing at true 10bit BT2020 would negate the HDR title as it would just be working in its native format limits. (unless you we're stretching the limits off that sensor maybe!)
In HDR delivery it sounds like Im missing something?

EDIT Tom Arrow commented before i finished posting again lol, and you are certainly not full of shit Wink
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#20
Oooooh, now I get your confusion. Okay, this must be clarified. The HDR photography technique you describe (layering various exposures over each other) has absolutely nothing to do with the term HDR when it comes to UHD Blu Rays. It's thematically related in that it has to do with a higher dynamic range, but that's where the similarities end. It also must be noted that the low dynamic range is not always the sensor's fault. Anyone who's ever taken a RAW picture with a DSLR will know that it has more details in shadows (and depending on the model, highlights) than the JPG produced by the same camera. Manufacturers artificially limit their sensor's dynamic range in the firmware. They prefer to have a "punchy" image because that what looks good at first sight in the store I think, so people are more likely to buy it. The other aspect is that they like to keep the unlocked dynamic range to their higher paying customers - even if its simple to implement.
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