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Does anyone know if a list exists showing which UHD media was mastered at 1000 nits vs. 4000 nits? When calibrating UHD displays, it appears necessary, at least on some displays, to have separate settings based on this, so a list would be handy to tell which settings to use when watching a particular title.
 

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Does anyone know if a list exists showing which UHD media was mastered at 1000 nits vs. 4000 nits?
Why would this matter for end user displays? I thought the only display currently available to anyone that can produce 4000 nits is the Dolby Pulsar display. Am I mistaken?
 

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Why would this matter for end user displays? I thought the only display currently available to anyone that can produce 4000 nits is the Dolby Pulsar display. Am I mistaken?
Your display still has to tone map, for content graded on the Dolby Pulsar.

Although, it doesn't mean the brightest pixel will be close to that, the titles that do, maybe you can increase contrast for a higher peak brightness.

Sent from my SM-G360T1 using Tapatalk
 

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My Oppo udp-203 report 4000nit for Blade Runner 2049, not 10000. Don’t sure if EU version (my) is different :confused:
Hi, the US version of Blad Runner 2049 has 10000 nits metadata, the UK (and probably other EU version) have 4000 nits.

OPPO is not reporting the Primaries/White Point cordinates of the mastering monitor or MaxCLL / MaxFALL also.

US Blade Runner 2049 mastering monitor had REC.2020 Primaries while UK had DCI-P3 primaries (always REC.2020 is used as container and it's the colorspace you aim as target when you calibrate for HDR10/DV)

See a quick example of what differences some movies (and a lot of others will have when the list will be available) have between regions (while UHD don't have region code restriction)....interesting differences:



Looks like Blade Runner 2049 is the first movie mastered with 10000nits monitor using REC.2020 primaries.

Blade Runner 2049 is the second title which has REC.2020 primaries, there is another one from BBC US: Wild Africa/ Tiny Giants (but mastered using a 4000 nit monitor).

There 2 ways to calibrated a Studio Mastering Monitor, one is to calibrated it for DCI-P3 with REC.2020 D65 and at the end to put these data to a REC.2020 container and the other way is to calibrated the monitor to REC.2020 directly; to take advance a monitor which has higher coverage from DCI-P3.
 

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Why would this matter for end user displays? I thought the only display currently available to anyone that can produce 4000 nits is the Dolby Pulsar display. Am I mistaken?
Hi, each display is doing different tone mapping according to the movie metadata, some displays don't do anything, some are roll-off sooner when they will see 4000nits (like 2017 LG OLED's), others don't do anything (like 2016 LG OLED's....if you send 1000 or 4000), others like Panasonic EZ1000 is counting MaxCLL also, but not all values; it's ignoring any MaxCLL below 401nits and above about 5000 nits. If you pause a frame and send different MaxCLL with HD Fury, the picture will change, it can be measured also what its doing by taking greayscale sweep.

For these reasons with HDR10 and static metadata, because there no golden standard about what tone/gamut mapping the HDR10 displays will perform with each movie incoming metadata, it's up to display model/brand/firmware that strategy will follow (clip/soft roll-off etc).

Dolby Vision bypass each display model/brand tone mapping and its using their own (Dolby's) defined tone/gamut mapping algorithm, per frame, so its more accurate.

The funny thing I have noticed is that subtitles also change slightly shade and luminance when you watch a DV movie from OPPO.
 

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hi viperlogic,
what does MaxCLL and MaxFALL mean?
Hi, a complete HDR10 metadata contains info about Mastered display used details (white point/primaries cordinates, max/min luminance) and Content Metadata info (MaxCLL + MaxFALL).

MaxCLL = brightest sub-pixel of a frame (nits)

MaxFALL = max APL of entire frame (nits)

For that calculation of Content Metadata (MaxCLL & MaxFALL) you need the RAW 16-TIFF frame master of a movie and the calculation should be performed before encoding to UHD-BD HEVC.

There a lot of movies which has MaxCLL & MaxFALL to 0 nits....(usually the 20th Century Fox releases), others are using a typical default which BDA is recommending to be 1000 MaxCLL /400 MaxFALL, others have calculated numbers (which is unknown if they are correctly calculated)
 

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Your display still has to tone map, for content graded on the Dolby Pulsar.

Although, it doesn't mean the brightest pixel will be close to that, the titles that do, maybe you can increase contrast for a higher peak brightness.
When we say ''4000 nits monitor used'' doesn't mean that the movie will have up to 4000 nits levels, it can have much lower or much higher, look examples below:






Mastering using 1000/4000 nits capable monitor a lot of times can contain brighter content from 1000/4000nits, just the colorist look the waveform and RGB histogram and leave un-clipped content above 1000/4000nits.
 

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When we say ''4000 nits monitor used'' doesn't mean that the movie will have up to 4000 nits levels, it can have much lower or much higher, look examples below:






Mastering using 1000/4000 nits capable monitor a lot of times can contain brighter content from 1000/4000nits, just the colorist look the waveform and RGB histogram and leave un-clipped content above 1000/4000nits.
Understood. Got a question for you. ICtCp has been touted by Dolby as the proper color model for HDR as it is absolute like EOTF PQ. When I read Dolby white paper on it, it also suggest that it best serves Rec.2020 compared to YCbCr which has issues maintaining hue linearity at high brightness values for color.

So why hasn't it been chosen as the color model standard for HDR content? Currently Netflix use the color model for all its new DV grades.

Last question is about, Contrast control in relation to Dolby Vision chipset based dynamic tone mapping. Display manufacturers tone mapping, from what I understand is tied to the display Contrast control, so a contrast control increase limits tone mapping retained detail.

Is this the case for DV?

I tested this, not with a meter but with just looking at content. Visually there's more detail, more cloud detail.

So if you can test DV, that would be awesome,thanks.



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Hi, the US version of Blad Runner 2049 has 10000 nits metadata, the UK (and probably other EU version) have 4000 nits.

OPPO is not reporting the Primaries/White Point cordinates of the mastering monitor or MaxCLL / MaxFALL also.

US Blade Runner 2049 mastering monitor had REC.2020 Primaries while UK had DCI-P3 primaries (always REC.2020 is used as container and it's the colorspace you aim as target when you calibrate for HDR10/DV)

See a quick example of what differences some movies (and a lot of others will have when the list will be available) have between regions (while UHD don't have region code restriction)....interesting differences:



Looks like Blade Runner 2049 is the first movie mastered with 10000nits monitor using REC.2020 primaries.

Blade Runner 2049 is the second title which has REC.2020 primaries, there is another one from BBC US: Wild Africa/ Tiny Giants (but mastered using a 4000 nit monitor).

There 2 ways to calibrated a Studio Mastering Monitor, one is to calibrated it for DCI-P3 with REC.2020 D65 and at the end to put these data to a REC.2020 container and the other way is to calibrated the monitor to REC.2020 directly; to take advance a monitor which has higher coverage from DCI-P3.
Ted, have you considered adding streamed UHD/HDR content to this list? In the US, Netflix and Amazon are providing a fair amount of HDR content. I know that streaming sources will be more compressed and of lesser quality, but it would still be useful to have them added to these lists.

Also, if these movies are provided on streaming services such as VUDU will they feature the same metadata?
 

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Understood. Got a question for you. ICtCp has been touted by Dolby as the proper color model for HDR as it is absolute like EOTF PQ. When I read Dolby white paper on it, it also suggest that it best serves Rec.2020 compared to YCbCr which has issues maintaining hue linearity at high brightness values for color.

So why hasn't it been chosen as the color model standard for HDR content? Currently Netflix use the color model for all its new DV grades.

Last question is about, Contrast control in relation to Dolby Vision chipset based dynamic tone mapping. Display manufacturers tone mapping, from what I understand is tied to the display Contrast control, so a contrast control increase limits tone mapping retained detail.

Is this the case for DV?

I tested this, not with a meter but with just looking at content. Visually there's more detail, more cloud detail.

So if you can test DV, that would be awesome,thanks.
HDR10 is 2160p YCbCr 10-bit, and Dolby Vision is adding a 12bit 1080p layer which is now is YCbCr 4:2:0 now.....YCbCr 4:2:2 in the future....and probably about @ 2019-2020 YCbCr will be replaced with ICtCp...then the DV discs will be encoded with ICtCP.

The problem is the format compatibility, I mean the last 3 years there exist HDR disk, you can playback DV from OPPO only (Not all TV's are supporting DV also), so when they release a movie, it has to support at least HDR10 where all HDR TV's are supporting, for that reason it's still at YCbCr.

To have a complete ICtCp, they have to been released in market disks only with DV version of the movie, which I found very difficult becasue it will sell only a few compared to HDR10/DV release.

According to Dolby ICtCp is better, but there experiments where they have found weaknesses also, the group called ''Joint Collaborative Team on Video Coding (JCTVC)'' has performed some testing comparing non constant or constant luminance YCbCr vs. ICtCp.

With streaming of DV, sure it's encoded using ICtCp becasue it's native DV delivery format, they have no reason to deliver with YCbCr.

Generally with DV mode, companies have to disable any calibration control which can confuse users or give the capability of user adjustments with tone mapping active and let calibration controls active only during calibration without DV tone/gamut mapping active, like its happening with LG 2017 and will happen with LG 2018 also.

BTW there some movies where their additional DV layer is not adding any additional detail, except the per frame metadata, a good example is the movie 'The Dark Tower', where the HDR10 layer has average bitrate 55116 kbps and DV layer bitrate only 122 kbps average.
 

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Ted, have you considered adding streamed UHD/HDR content to this list? In the US, Netflix and Amazon are providing a fair amount of HDR content. I know that streaming sources will be more compressed and of lesser quality, but it would still be useful to have them added to these lists.

Also, if these movies are provided on streaming services such as VUDU will they feature the same metadata?
Hi, metadata can be grabbed using HD Fury, where you put the device between source/display and you can grab HDR10 static metadata only. For that reason you need a source that can play HDR10 which is separate from display, like Apple TV, you can grab from there metadata.

There no way to grab any (per frame) metadata DV signal sends.

When I will have the site page ready, with the metadata list, I will have info about how to grab metadata for new users to be able to hook me up with metadata from any device, so to be possible to know what is happening with stand-alone streaming devices also ;)
 

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HDR10 is 2160p YCbCr 10-bit, and Dolby Vision is adding a 12bit 1080p layer which is now is YCbCr 4:2:0 now.....YCbCr 4:2:2 in the future....and probably about @ 2019-2020 YCbCr will be replaced with ICtCp...then the DV discs will be encoded with ICtCP.

The problem is the format compatibility, I mean the last 3 years there exist HDR disk, you can playback DV from OPPO only (Not all TV's are supporting DV also), so when they release a movie, it has to support at least HDR10 where all HDR TV's are supporting, for that reason it's still at YCbCr.

To have a complete ICtCp, they have to been released in market disks only with DV version of the movie, which I found very difficult becasue it will sell only a few compared to HDR10/DV release.

According to Dolby ICtCp is better, but there experiments where they have found weaknesses also, the group called ''Joint Collaborative Team on Video Coding (JCTVC)'' has performed some testing comparing non constant or constant luminance YCbCr vs. ICtCp.

With streaming of DV, sure it's encoded using ICtCp becasue it's native DV delivery format, they have no reason to deliver with YCbCr.

Generally with DV mode, companies have to disable any calibration control which can confuse users or give the capability of user adjustments with tone mapping active and let calibration controls active only during calibration without DV tone/gamut mapping active, like its happening with LG 2017 and will happen with LG 2018 also.

BTW there some movies where their additional DV layer is not adding any additional detail, except the per frame metadata, a good example is the movie 'The Dark Tower', where the HDR10 layer has average bitrate 55116 kbps and DV layer bitrate only 122 kbps average.
So can contrast be adjusted independently from tone mapping for DV?

I wonder if the same rules apply to the Contrast control as it does with SDR content. Increasing contrast means the risk of clipping white detail. Or you would get a pink hue in white, because you have exceeded the display limited RGB luminance.

Since you're no longer tied to SDR peak limits 100 cd/m2, we should have more headroom to tweak peak white and adjust contrast. Assuming you can adjust the lower end of the EOTF PQ.

If I were to calibrate using ICtCp, could it help YCbCr coordinates track better? Maybe look at it like a color model container. Or are you still dealing with the same color coordinates?

Sent from my XR6P10 using Tapatalk
 

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So can contrast be adjusted independently from tone mapping for DV?

I wonder if the same rules apply to the Contrast control as it does with SDR content. Increasing contrast means the risk of clipping white detail. Or you would get a pink hue in white, because you have exceeded the display limited RGB luminance.

Since you're no longer tied to SDR peak limits 100 cd/m2, we should have more headroom to tweak peak white and adjust contrast. Assuming you can adjust the lower end of the EOTF PQ.

If I were to calibrate using ICtCp, could it help YCbCr coordinates track better? Maybe look at it like a color model container. Or are you still dealing with the same color coordinates?

Sent from my XR6P10 using Tapatalk
Contrast/OLED Light has to been disabled for HDR10/DV mode to any TV model since they affect the internal display tone/gamut mapping.

ICtCp/YCbCr are compression encoding formats used for delivery, the coordinates defined by the CIE XYZ chart you are using for each target colorspace, so they don't change.
 

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I think the MaxCLL/FALL values for Blader Runner 2049 (US) might be incorrect. Vertex is reporting 500/200.
 

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I think the MaxFALL/CLL values for Blader Runner 2049 (US) might be incorrect. Vertex is reporting 500/200.
Hi, Blade Runner 2049 (USA) has been checked from 2 different people and has the metadata I posted. Do you have the actual disk? Because many Remux of various movies using 500/200 as default and incorrect for all releases.

What player do you have?
 

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Hi, Blade Runner 2049 (USA) has been checked from 2 different people and has the metadata I posted. Do you have the actual disk? Because many Remux of various movies using 500/200 as default and incorrect for all releases.

What player do you have?
I was testing an .iso image created from the US release; it's not a remux. MediaInfo reports the same 500/200 values from the main feature m2ts.
 

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I was testing an .iso image created from the US release; it's not a remux. MediaInfo reports the same 500/200 values from the main feature m2ts.
The guy responsible for the iso has done the error, we have checked real disks.
 
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