Studio 15 + GH5 & HLG for HDR output?

Hi,

I'm using Studio 15, with 4K/30 Lumix GH5 HLG (10bit 4:2:2) files with a goal to output in HDR. I have the workflow "working" by using Studio 15 to output to DNxHR files, and then using MyFFMPEG to convert that to HEVC .mp4 files.

However, the contrast is crazy high, the whites get totally clipped and the blacks have no detail either.

I am a new user to Resolve so I'm not sure what the problem is, but I *think* the issue is in the Color Space & Transforms page where I can't figure out the optimal setting for GH5/HLG/HDR projects.

Here's what I've tried:
Color Science: ACEScc
ACES Version: ACES 1.0.3
Use Separate Color Space and Gamma: unchecked
Next 6 options are greyed out
ACES Input Device Transform: I've tried "Panasonic V35" and "Rec.2020 ST2084 (1000 nits)"

ACES Output Device Transform: Rec.2020 ST2084 (1000 nits)
Process Note LUTs in: ACEScc AP1 Timeline Space
HDR Mastering: Checked & 1000 nits.

I've checked the Scopes, and they look reasonable, nothing going over 1000 nits.
And under Preferences->Color->User->Enable HDR Scopes for ST.2084 is checked

When I use the Panasonic V35 (the only Panasonic setting I see) the blacks are crushed, the whites clipped. When I use the Rec.2020... the blacks are improved, but the whites even worse.

I'm fairly certain my problem is the configuration within Resolve, not MyFFMPEG, but none the less, for completeness, my settings in MyFFMPEG:

H.265 Main Profile 10bit
Pixel Format (YUV420p10le)
Color Options: Color Primaries: BT.2020
Color Options: Color Trasfert Characteristics: SMPTE ST 2084
MaxCLL 1000
MaxFALL 400
Force Signaling for HDR parameters in SEI Packets


Please help

Roland.

The first step is to see which half of the chain is broken. What do you see when you play your DNxHR files on your HDR display? If that's no good, your FFMPEG can't make it better. If the DNxHR files play as you expect, then your FFMPEG parameters are the problem.

The current version of ACES does not support HLG. If you want to use HLG use RCM with Rec2100 HLG as input.

Rec2020 ST2084 uses a display referred PQ curve not a HLG curve.

Edited to add: Paul Dore made an ACES 1.1 DCTL which includes HLG.
https://github.com/baldavenger/ACES_DCTL

I wonder if BlackMagic will have 1.1 in Beta6.

[Peter Chamberlain]

Roland, try those files in RCM and not ACES.

Thank you for the suggestions your help was the vital link to success! As this thread has been viewed a few hundred times by others potentially looking for the same answers I figured I would reply with an update and the path I used.

Original source was GH5 content recorded in HLG mode, and I wanted an .mp4 HEVC output file....


1. Setup the Scopes for HDR:
Resolve->Preferences->User->Color->Enable HDR Scopes for ST.2084

2. Setup the Project for HDR:
File->Project Settings->Color Management
Color Science = DaVinci YRGB Color Managed
Input Color Space = Rec.2100 HLG
Timeline Color Space = Rec.709 Gamma 2.4
Output Color Space = Rec.2100 ST2084
Timeline to Output Tone Mapping = None
Timeline to Output Gamut Mapping = None
                      HDR Mastering (checked) set to 1000.


I then output the project from Resolve as DNxHR 444 12-bit (gigantic file: 50GB for ~ 4minutes)

Then I downloaded MyFFMPEG (18 Euros) to convert the DNxHR file into a HDR .mp4 H.265 file.

For HDR Output: Change the Target settings to:
o General Options
○ MP4 container (.mp4)
o Video
○ H265
o Video->Edit
○ H265
○ Pixel Format YUV420p10le
○ CQF 25
○ BitRate Preset Manual
○ Bitrate 40000

Video->Advanced->X265 Options Part 1
○ Profile Main 10
○ Preset Medium (quick encode) Very Slow (highest quality)
o Video->Advanced->X265 Options Part 4
○ Max content and Max frame average light level, Checked, 1000, 400
○ Force signaling of HDR parameters in SEI packets



o Video->Advanced->Color Options
○ Color Primaries BT.2020
○ Color Transfert Characteristic SMPTE ST 2084

o Audio
○ MP3
○ Channel Specifier - Default (Stereo)
○ Bitrate 320Kbps

I hope that's useful to anyone trying something similar to what I wanted to get working. I'm very pleased with the result. Now I just need to figure out how to get HDR preview during editing to work.

Roland.

Timeline Color Space = Rec.709 Gamma 2.4

The Gamma is ok but I would not use a Rec.709 gamut.
I would keep it Rec.2020.

Yep, don't use Rec.709 there as you limiting gamut to Rec.709 as middle step even if output is Rec.2020 (GH5 most likely uses Rec.2020 so it definitely records more than Rec.709).
Why gamma 2.4? So you mastering to 2.4 and then on output convert to PQ? This doesn't make sense for me.
Timeline settings should be: P3 ST2084 (assuming your grading monitor is close to P3)- so you grading to HDR PQ with gamut set to P3 (most HDR TVs are close to P3). Then during encoding you need to store info that mastering display is P3.

"Max content and Max frame average light level, Checked, 1000, 400"- these are not constant values, but they need to be measured once you have final HDR master.

Don't use Very Slow preset with x265- takes a lot of time. Medium/fast is good enough, just raise bitrate to eg 70Mbit.

I'm only using the one PC monitor, no grading monitor yet. Because Resolve is limited to sRGB/709 being an SDR app in windows this seems to be the best set of options. I will give your suggestions a try, but I suspect you are assuming a second grading monitor

Sent from my SM-G950U using Tapatalk

Yes, you need HDR P3 with gamut grading monitor (on normal monitor results will be very wrong)- use your TV over BM card.
Your approach is quite a big compromise. You are grading SDR master and then converting to HDR by math. Not most optimal approach.

Why gamma 2.4? So you mastering to 2.4 and then on output convert to PQ? This doesn't make sense for me.

All the timeline gamma does in the above scenario is to determine how the controls actually work against the given curve. You could use linear, gamma 2.4, log, basically whatever you like. But gamut is another matter.

So which settings do determine GUI/monitoring preview gamma?
For GUI preview it's timeline gamma+output as far as I can tell (at least on Mac with color managed viewers), which means setting it to whatever gives you totally wrong preview. It should be set to whatever your GUI monitor is set to. If you have Rec.709+2.4 calibrated monitor this in theory should give you accurate preview (for Rec.709+2.4 settings in Resolve).
I assume in case of BM preview I can have timeline set to 2.4, but still monitor over BM card as HDR PQ. There still has to be something which controls what Resolve sends to actual BM card, output color space?

So which settings do determine GUI/monitoring preview gamma?

The output color space transforms (except when you use bypass).

For GUI preview it's timeline gamma+output as far as I can tell (at least on Mac with color managed viewers), which means setting it to whatever gives you totally wrong preview.

It isn't, it is the output color transform that matters (again with exception of all the buts and ifs wrt bypass).

The output color transform should be set equal to the settings of your monitor.

The timeline gamma determines how the Resolve operators affect the image, for instance, a LGG adjustment would have a different effect on the log, linear or PQ curve). Typically you would want to use the log operators for log and the regular LGG for linear, Rec.709 or true gammas.

I'm only using the one PC monitor, no grading monitor yet. Because Resolve is limited to sRGB/709 being an SDR app in windows this seems to be the best set of options. I will give your suggestions a try, but I suspect you are assuming a second grading monitor

Then all your bets are off, you simply cannot visually color correct, let alone grade, an HDR video using an SDR monitor.

Cary - yup, I recognize that. However, I'm just trying to find the best arrangement given the limitation of the hardware I have and Studio 15.

I have a Windows 10.RS4 HDR PC, and HDR monitor (Asus PG27UQ), however Studio 15 only runs in SDR mode, and doesn't take advantage of the HDR monitor at all. Without a BM Mini Monitor 4K card and second monitor I'm trying to do the best I can with the single monitor setup.

Given my input is GH5 HLG HDR files, in BT.2020 gamut, and my planned output is .mp4 HEVC Bt.2020 HDR files. Is there anything suboptimal about my current settings:

Color Science = DaVinci YRGB Color Managed
Input Color Space = Rec.2100 HLG
Timeline Color Space = Rec.709 Gamma 2.4
Output Color Space = Rec.2100 ST2084
Timeline to Output Tone Mapping = None
Timeline to Output Gamut Mapping = None
HDR Mastering (checked) set to 1000.

The above combination seems to yield HDR output files, and seems to provide the best (albeit still pretty poor) preview capabilities. If there's a better combination of settings I would love to try them.

I'm ever hopeful that Studio 16 will include HDR support into the application, and this whole problem is solved for the single HDR monitor user.

Roland.

The timeline gamma determines how the Resolve operators affect the image, for instance, a LGG adjustment would have a different effect on the log, linear or PQ curve). Typically you would want to use the log operators for log and the regular LGG for linear, Rec.709 or true gammas.

Well- definitely not on Mac with color managed viewers. Timeline settings affect preview as well as output color space. Maybe this is yet another reasons why GUI preview should not be used for grading in Resolve.

Whole thing doesn't make sense. Key setting should be timeline. Output setting should be moved to export tab and there you can from your main settings convert (by pure math) to other outputs. This was mentioned in other post.

Cary - yup, I recognize that. However, I'm just trying to find the best arrangement given the limitation of the hardware I have and Studio 15.

I have a Windows 10.RS4 HDR PC, and HDR monitor (Asus PG27UQ), however Studio 15 only runs in SDR mode, and doesn't take advantage of the HDR monitor at all. Without a BM Mini Monitor 4K card and second monitor I'm trying to do the best I can with the single monitor setup.

Given my input is GH5 HLG HDR files, in BT.2020 gamut, and my planned output is .mp4 HEVC Bt.2020 HDR files. Is there anything suboptimal about my current settings:

Color Science = DaVinci YRGB Color Managed
Input Color Space = Rec.2100 HLG
Timeline Color Space = Rec.709 Gamma 2.4
Output Color Space = Rec.2100 ST2084
Timeline to Output Tone Mapping = None
Timeline to Output Gamut Mapping = None
HDR Mastering (checked) set to 1000.

The above combination seems to yield HDR output files, and seems to provide the best (albeit still pretty poor) preview capabilities. If there's a better combination of settings I would love to try them.

I'm ever hopeful that Studio 16 will include HDR support into the application, and this whole problem is solved for the single HDR monitor user.

Roland.

Nothing you can do better with current hardware.
You can get BM card and feed your Asus HDR monitor from it for HDR preview, but this monitor is probably way of the 1000nits standard, so this is most likely not worth it.

Nothing you can do better with current hardware. You can get BM card and feed your Asus HDR monitor from it for HDR preview, but this monitor is probably way off the 1000nits standard, so this is most likely not worth it.

OK I'm ordering the card today. But the Asus monitor is great. I measured 1118 nits max (10% patch), 1091 nits full screen 100% white patch. >97% DCI-P3, >83% BT.2020. There are few displays out there that can match this level of performance.

It's just rather cumbersome from a software perspective that I have to use two monitors and a Decklink card to actually get this working in HDR.

Roland.

GUI preview in Resolve is not designed to be color accurate. Maybe it can be achieved at the end, but specially with HDR it can be very problematic. There is also no way to have 2nd full screen GUI preview in Resolve nor a guarantee for proper sync between timeline fps and monitor.
If your monitor is decent, calibrate it, get BM card and use it with your monitor for clean video feed.
With for example Assimilate Scratch you can do it just over graphics card (not sure about HDR though).

Monitor looks decent as for gaming one:
http://www.tftcentral.co.uk/reviews/asu ... pg27uq.htm

Not sure if it can properly display HDR PQ signal though. There is enough brightness, but whole accuracy to PQ curve is another question.

looking at this thread I have some questions as I also have the GH5 and want to use HLG 10bit as it output (for my eyes) more dynamic range and easier color grading (results looks good when converting to 709),
first question, what is the workflow settings if I want to shoot in HLG but work in 709?
Also I want to buy a new 10bit monitor (true 10bit) which one you are recommending? DELL UP2718Q as the specs are great and price now is lower
Which BM card I need to output HDR?

thanks

looking at this thread I have some questions as I also have the GH5 and want to use HLG 10bit as it output (for my eyes) more dynamic range and easier color grading (results looks good when converting to 709),
first question, what is the workflow settings if I want to shoot in HLG but work in 709?

I would recommend this:

hlg---settings.jpg (96.76 KiB) Viewed 5417 times

Change the timeline gamma to your liking. Some people prefer to grade with a Rec.709 curve (use the LGG controls) while others prefer a log curve (use the log controls), you could even use a PQ curve with HDR mode, but I would avoid an HLG curve because it is hybrid Rec.709/log. Gamut mapping is optional, instead, you could do it yourself in the nodes. Also, I would not use the tone mapping functionality at the project level.