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Discussion Starter #1 (Edited)
CONTENTS FILM LIST (This will be constantly updated):

Alien Covenant

Blade Runner
Blade Runner 2049
Blue Planet II
Deepwater Horizon
Interstellar
John Wick 2
Lucy
Mad Max
Passengers

Patriots Day
Spiderman Homecoming
The Matrix
The Revenant


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Hey Guys,

I am posting this in its own thread here in the projector forum since I think this information is really useful regarding HDR on projectors specifically since its clear all of us are viewing HDR at a less than ideal peak brightness level, and certainly not at the level intended by the creators of the content. As such our displays have to use tone mapping and gamma curves to arrive at the best possible compromise, and to do that, one must know a little more about the way the content is mastered.

I think this info will be a good reference to see what is really happening with some of the UHD BR titles out there, we will look at the HDR Grading of these films represented in a waveform using the Black Magic Design Davinci Resolve colour grading software. This is the very same software that quite a lot of hollywood films are graded on, and certainly a lot of UHD Blurays are HDR mastered and even remastered in also.

Recently its come to the attention of the general forum that UHD Bluray titles are 'mostly' mastered with black levels down to black 64 on the clipping pattern. Which is 0 nits. Now up until now we assumed based on the metadata associated with the discs that there was a great number of titles, almost half, that are supposedly mastered to 0.005 nits. As such, most of us have been configuring our HDR curves and calibrations to set black clipping to bar 77 as true black, which is 0.005 nits. However we now know that in actual fact, most titles save for a handful so far are really 0 nits. I sought to confirm this in the manner that makes the most sense to me and that is to look at a physical waveform of the film and see what's really going on.

There is a really good spreadsheet which is constantly being updated that contains HDR Metada on a lot of HDR titles, we have mostly been using this unto this point to ascertain certain information on titles.

UHD Bluray HDR Metadata

But I feel we can expand on this, using these waveforms we can also get a really good indication of where most of the real brightness sits on the scale and what it looks like when there are brighter specular highlights etc.

Hopefully we can all use the information in this thread, which will be added to as time goes on, to come to a really good HDR setup personalised for yourself, while targeting peak white levels to suit your own situation, some people may have been using 1000nits as the out of the box clipping level on some Sony projectors for example, some of you may have been using a single 4000 nit calibration. We hope to show here how much content actually exists above 1000 nits, what kind of content it is, and weather some of you with light starved projector and screen combinations may be able to either sacrifice certain things and run lower peak white targets, or at least, make a well informed decision on how to set up your projector for HDR.

This will be a good place to have a look and compare the brighter HDR grades with dimmer titles, some of you may have watched films that you just couldn't understand why the title looked quite dark compared to others, well, we can dive into that here and hopefully if I can get access to said films, we can look at whats really going on in specific scenes.

I will start by submitting a baseline in regards for how to actually read these waveforms.

The waveform in colour grading is a visual representation of the image brightness and colour information from left to right, if you study the waveform next to the image you will begin to get an idea of how the waveform works, the bottom of the scale is black, and the top of the scale is white, or peak output in brightness, the scale all the way at the top or 1023 on the scale is 10,000 nits. No film is mastered to such levels at the moment and probably will not be for quite some time. On the scale you will see 768 also, that is 1000 nits peak output. And for 4000 nits, you will see a faint grey line right at about value 920. Now most of us with either have HDR configured for 768 or 920, most titles are mastered at one of these two values, now what we want to see is what it really looks like with films that say they are mastered to a certain level, do they take advantage of the whole 'container' if you will, or are they falling significantly below the mastering level?

Here is a white clipping chart, you will see from left to right a range in brightness and I have highlighted 1000 and 4000 nits, so you can get an idea when looking at other waveforms where they sit on the scale. You will also see 94 nits on the scale sits right around level 512, this is diffuse white, most of the content in any given frame is going to sit below this point, for eg people faces, clothing etc... if it did not the scene would likely appear to be overly bright and a little intense.



As said the bottom of the scale is black, which is 0 nits, now just above that you will see 0.005 nits, this can be seen on the following image, we should be paying attention to these points, does the waveform fall all the way to the bottom or does a particular film hover just above the bottom closer to 0.005 nits, if so, then that film has a raised black level, and if you are clipping your HDR set-up to Bar 64, or 0 nits black then that film will have a more grey appearance and raised blacks.



On the flip side, we will also see a lot of important content below 0.005 nits on the titles that have true black levels of 0 nits, these waveforms will shot where that content is, and what you are missing. Unfortunately with the state of HDR as it is today, this should ideally not even be a consideration, ALL titles should be black level of 0 nits, the fact that some titles are 0 and some are 0.005 makes it difficult for us to have a one fits all solution for HDR on projectors, and unfortunately we will need either separate user modes for these differing black levels and significantly differing average brightness, or we just choose one or the other and live with it.

NOTE - The below screenshotts will appear to be washed out and not very saturated, this is because they are viewed in log form in this software, since the end display is the one which needs to be in an HDR mode to view it. In fact, those of you viewing the forum with HDR displays will actually be able to see these screenshots if you switch your display to HDR mode. That should be interesting.
 

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Discussion Starter #2 (Edited)
To start off, I will list each film in its own post, and if I add to it, I will come back and edit the post and include more images. I will also slowly include all the proper metadata from the above linked spreadsheet as a point of reference. So bare with me.

Mad Max.

4000 nit film, supposed to be 0.005 nits black, but its not, as expected, but also interesting it has some highlight info that sails right past 4000 nits!

Max Nits 4000
Black Level 0.005 Reported, but actually 0 nits true black.
Max CLL 9919
Max FALL 3242



 

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Discussion Starter #3 (Edited)
Lucy.

These blacks are actually 0.005 nits in real live action content, but the black screens are well past that and they are actually hitting level 81!

Max Nits 1000
Black Level 0.005 Some content actually ABOVE this, the black titles screens for eg
Max CLL 1000
Max FALL 400





 

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Discussion Starter #5 (Edited)
Alien Covenant.

An interesting one, seems like 0.005 nits (Bar 77) blacks, but I did find a shot (And I wasn't looking very hard either) that had proper black 64 content. I think for this film its best to assume bar 77 0.005 nits black if the space scenes remaining quite inky black is important to you.

Max Nits 1000
Black Level 0.005 Reported, but actually 0 nits true black.
Max CLL 0 - Not reported via EDID Metadata
Max FALL 0 - Not reported via EDID Metadata





This one has content down to 64 true black...

 

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Discussion Starter #10 (Edited)
Patriots Day.

I don't have the metadata for this film, if someone does, please let me know and I will add it.

Appears to be a 1000 nit title with 0.005 nits black.

For broad daylight scenes screen-shotted here, this has most of its content rather low on the waveform, if you compare this to brighter films such as Lucy or John Wick, you will see that in fact, this film is a dark one compared to others.





 

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Discussion Starter #11 (Edited)
Blade Runner 2049.

This most definitely has some content down to true black 64, however most of the film sits purposefully above that.

Max Nits 4,000
Black Level 0.005 Reported, but actually 0 nits true black.
Max CLL 457
Max FALL 179















The below is a very tough scene, you must be set to black 64 to resolve the information in the shadows here:















 

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Blade Runner 2049
On this title even though it's mastered at 10,000, it would be recommended to use a curve optimized for 1,000 max nits, correct? Since it looks like nothing exceeds 1,000 based on the MaxCLL?

Awesome analysis by the way...would really appreciate this on many films to ensure us laymen have a better shot at starting with the correct settings.

Also if using curves set for 64 (0 nits), and encountering a raised title like Lucy, is the advice to just lower brightness in the UHD player or projector itself by a couple of clicks to -2 or -3? Same with something like Covenant to maintain the blackness of space scenes?
 

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Great thread.

I've kept an old Panasonic projector around partially because it has a waveform monitor, but I believe that is only useful for SDR. Glad to see you found a way to get waveform information for HDR content.

--Darin
 

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Discussion Starter #15
On this title even though it's mastered at 10,000, it would be recommended to use a curve optimized for 1,000 max nits, correct? Since it looks like nothing exceeds 1,000 based on the MaxCLL?

Awesome analysis by the way...would really appreciate this on many films to ensure us laymen have a better shot at starting with the correct settings.

Also if using curves set for 64 (0 nits), and encountering a raised title like Lucy, is the advice to just lower brightness in the UHD player or projector itself by a couple of clicks to -2 or -3? Same with something like Covenant to maintain the blackness of space scenes?
Correct on both counts

Best thing to do would be to setup your permanent curve for 64 black but also when you do that just see how many clicks on brightness it takes to clip to 77 and then remember it so you know for future reference.
 

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Discussion Starter #16
Great thread.

I've kept an old Panasonic projector around partially because it has a waveform monitor, but I believe that is only useful for SDR. Glad to see you found a way to get waveform information for HDR content.

--Darin
Thanks Darin, I definitely hope to add many many films to this. I actually set up a script yesterday to screenshot mine all my uhd films so It should make it easier for me to start getting the bulk of them in this thread.
 

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On this title even though it's mastered at 10,000, it would be recommended to use a curve optimized for 1,000 max nits, correct? Since it looks like nothing exceeds 1,000 based on the MaxCLL?

Awesome analysis by the way...would really appreciate this on many films to ensure us laymen have a better shot at starting with the correct settings.

Also if using curves set for 64 (0 nits), and encountering a raised title like Lucy, is the advice to just lower brightness in the UHD player or projector itself by a couple of clicks to -2 or -3? Same with something like Covenant to maintain the blackness of space scenes?
Correct on both counts

Best thing to do would be to setup your permanent curve for 64 black but also when you do that just see how many clicks on brightness it takes to clip to 77 and then remember it so you know for future reference.
Awesome that's a good idea. Already adjusted both curves for 64 and am going to update the 1000 to 1200 tonight I think.
 

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Discussion Starter #18
Interstellar.

Max Nits 4000
Black Level 0.005 Reported, but actually 0 nits true black.
Max CLL 1242
Max FALL 436





This shot is just kissing level 77 black. Barely, you can actually see I have added a new grey line across the bottom which will be there in all future analysis, it represents level 77 black, so this scene has content beginning just a hair above that, which explains why my JVC DI didn't like to close down much on this shot.
















This is the brightest shot in the movie interestingly. This is the only shot that would be harmed if you watched this film to a clipping point of circa 1000nits. Looks like its about 1350-1400 nits. Despite MaxCLL being reported 1242, I think the MaxCLL number is inaccurate for this title. Only slightly. MaxCLL and MaxFALL data actually has to be manually added after the film is graded so there is every chance of an error like this popping up. We know based on the white clipping charts that the waveform is reading accurately, so I don't think its the waveform overshooting here.







 

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Great work Javs!! Always nice to read ur post and learn new things .

I watched Patriot Day yesterday and it definitetly was darker than other movies, its noticeable right away.
 
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Updated my curve to 1200 nits, and made sure black level was perfectly set to just barely flash (viewing from seating area) 68, with DI & Clear Black off.

Also checked and -2 brightness on the UB900 is perfect for both 1200 and 4000 curves to adjust so that just 77 is barely flashing.

Feeling pretty dialed in lol.

Need to pick up the UHD Interstellar I guess...although is it worth it if I already have the blu-ray? It's one of my favorite movies.
 
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