Originally Posted by PeteNeat
D-Nice, thank you for the enlightenment, I also have PE2 BlueRay and the scene changes are perfect black. Not only that the black of space from the Earth shots are also perfect black.
Naturally this makes my brain fart somewhat....
Hi, Planet Earth II HDR10 static metadata infoframe has 'zeros' to all it's Mastering Display Color Volume or Content Metadata. It's a conversion of HLG -> HDR10 and its peak output doesn't exceed 1000nits.
Mastering has been performed from [email protected]
(UK) which are using LightSpace for Calibration (it's at the LightSpace's customer list
) using a Dolby PRM-4220 Professional Reference Monitor (Dolby talking that one of their monitor features is the capability to use LightSpace for its calibration
), which is an SDR 1080p but high-brightness panel, real 12-bit panel with 100% DCI coverage, it can output about 600nits calibrated, but because it's RGB-LED it's not having the blacks of OLED's.
Dolby Monitor has 2x 65-Point Cube 3D LUT table uploading capability (same 3D LUT Cube size as eeColor 3D LUT Box we have in consumer market), so they used an HLG 3D LUT with FilmLight's Baselight color granding suite.
When you use a 600nit monitor for grading HDR content you can still grade for higher nits (for 1000 nits) if you not clip above 600 nits, leaving the highlights unclipped and evaluate using the software histograms.
For make metadata analysis, to find the Content Metadata (MaxCLL & MaxFALL) you need to have the RAW 16-TIFF master of the Planet Earth II and the calculation should be performed before encoding to UHD-BD HEVC.
Except Planet Earth II, there a lot of movies which has MaxCLL & MaxxFALL 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.
There displays, like the Panasonic EZ1000 which counting the MaxCLL number to their internal calculation, for example if you pause one HDR movie using Panasonic and send a different MaxCLL using HD Fury, you will see that the still picture will be change.
Basically consumer display don't follow specs completely or correctly this time, this is why the black level (and highlights also) performance of released UHD titles is varying, there movies which have lifted blacked, other with clipped near blacks etc.
About Black levels, in SDR, with 100nits as Reference White, the Target Luminance for Power Law Gamma 2.2 (with a display with 0 nits black, like OLED) is:
0.5% Gray (17 level) is 0.0007 nits
1% Gray (18 level) is 0.0033 nits
In SDR, with 100nits as Reference White, the Target Luminance for Power Law Gamma 2.4/BT.1886 (with a display with 0 nits black, like OLED) is:
0.5% Gray (17 level) is 0.0002 nits
1% Gray (18 level) is 0.0013 nits
In SDR we use Gamma curve as transfer function (where you can set it to 2.2/2.4/BT1886 or whatever value you like....having in calculation the display Black/Peak White level to generate each digital code luminance levels, but in HDR with PQ Curve transfer function, it has fixed numbers for each digital code luminance level (0-10.000nits) when you have a display; lets say an LCD-LED which has about 0.039 nits black level (Samsung 55KS9000 for example), all the near black information below that, from the 10-bit HDR signal will not be displayed, so it's lost.
So when you have a movie mastered with min 0.005 nits and you watch it with OLED which has 0 nits, it's up to the display internal programming what to do....
BT.2390 (which is not a published standard, it's a report) it has a minLum parameter to do a normalize counting to the display real black measurements but even if a display will follow that minLum parameter (which is baked inside to a display data) .....if BY.2390 was a spec and not just a report.../, how does a display know it's current black level measurement? ... There a lot of users talking for lifted blacks and glowing blacks even at using default setting to OLED's, also if a calibration adjustment from the user using the 127 digital point calibration setting adjustment (5% lets say) is high, this can affect the black level measurement. (of it the user have wrongly adjusted Contrast/Brightness,OLED Light to values other from default values.)
See also for example CalMAN 5 calculated 64-Point Grayscale luminance targets for ST.2084, based as example to Samsung UE55KS9000 measurement data (Black Level 0.039 nits - Peak White: 1460 nits), some near black will clip.
Adding Dynamic frame per frame features will just undo your calibration, since it will be changing the panel response, so at the end you don't see a movie how supposed to look but how LG want, preserving all details that you monitor can't display which will reduce the levels of your display...those who can correctly display and follow ST.2084 PQ, so the calibrated part of your display (0-750 nits) from the user menu adjustments it will be ignored and levels will be re-adjusted in real-time....if the mastering is from 4000 nits, the whole picture will be a lot darker compared to 1000 nit mastered movie.
This is the reason why calibrated displays in HDR mode will reproduce the most movies at average levels of color performance.
One of the solutions to this can be using HD Fury to calibrate using patterns with metadata... for example 1000nits max, 1000 MaxFALL, 400MaxCLL, and after the end of calibration enable from HD Fury to send the same metadata you used to calibrated to the display, so the display will always be receiving the same fixed metadata (to it will have fixed and calbrated response) to any movies you will watch...it will not be receiving each movie metadata.
If someone has HD Fury, he can try this and post some feedback, from watching 4000nits movies.
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:
So when you have that titles which their max luminance levels is below the max output of an OLED, it means that it will not have to use any roll-off since all data from the movie will be below the max panel output capability, but the most dislpays will see the 4000 max only and start the roll of a lot nits earlier so the total picture will be very dimmed.