Windows 11 24H2 Color Management

[Cynersi]

windows 11 24H2 redid the color management setting and now has this new setting (shown below)

when enabled, v4.2-fix cannot clamp due to reporting that "Windows is in HDR" when it is not. also the colors look SUPER washed when this setting is enabled while using an older version that uses the NVapi.

[hwfanatic]

I can confirm that the app is reporting "HDR is active - cannot clamp" when automatic color management is enabled in 24H2.
The strangest thing is I have never enabled this option, so I guess it is either enabled by default, or something is toggling it without my knowledge.

[casef]

I don't even have the option anywhere and srgb_novideo is still reporting HDR as active in SDR.

Edit: Nevermind, they moved it from Advanced Display Options to Color Profile (you have to click on the field where the dropdown button for profile selection is). I haven't had it enabled, but it seems like it might be getting stuck when you disable HDR or something, will have to test it more.

[digiw]

windows 11 24H2 redid the color management setting and now has this new setting (shown below)

when enabled, v4.2-fix cannot clamp due to reporting that "Windows is in HDR" when it is not. also the colors look SUPER washed when this setting is enabled while using an older version that uses the NVapi.

I'm in the same situation as you in win11 24h2! I'm also very confused, and if you select "Output Color Depth" as 10bpc in the NVIDIA graphics card control panel - "Use NVIDIA color settings", then there will be the same problem as you mentioned!

[hwfanatic]

If you enable 10 bpc output color depth in NVCP, this will enable automatic color management in Windows.
If you disable automatic color management in Windows, this will revert all color settings to default in NVCP.

[casef]

If by "revert all color settings to default in NVCP" you meant that it will disable the 10bit color enforcement, then I can certainly have 10bit forced in NVCP with ACM disabled. 24H2, 565.90 drivers.

Not that there's much point in forcing 10bit color in SDR, given that SDR apps don't really use 10bit color (with maybe a handful of exceptions).

[hwfanatic]

I mean that the settings are coupled. There is really no way to adjust these settings separately.

Enabling automatic color management will set the output color depth to 10-bit and disabling it will set the output color depth to 8-bit.

The opposite is also true. Setting the output color depth to 10-bit will enable automatic color management and setting it to 8-bit will disable automatic color management.

[casef]

@hwfanatic Automatic color management does seem to re-enable itself every time you adjust the color depth, yes. That might be a bug (at least I hope it is). However, you can absolutely have 10-bit color enabled and ACM disabled (or at least I can on current nVidia drivers) - just change the color depth to 10-bit (which will make Windows re-enable ACM if you had it disabled) and then go and manually disable ACM without touching the color depth.

You can't have ACM enabled with 8-bit color, but that's by design, as ACM seems to require at least 10-bit color to work. So yes, enabling ACM will force-enable 10-bit color.

But there are some other issues with ACM, for example, my monitor has a perfectly fine working sRGB clamp and it's enabled by default for all SDR content (as it should), but if I enable ACM for this monitor, it will read the primaries of the full gamut of the monitor, making the colors in SDR even more desaturated than they should be. To get proper colors with ACM enabled, I have to manually force my monitor to native gamut in SDR. sRGB_novideo does not have this issue and detects the monitor's sRGB clamp correctly when it is active.

And in general, it would be great if there was more information on how to use ACM and how to take advantage of what it can do. I would love to know how to correctly use color profiles with ACM (both in SDR and HDR, if possible), for example.

[Whitiger3000]

https://github.com/dantmnf/MHC2
this repository,a tool can be used to make color profiles for ACM,and information on what is ACM/how it works/how to use it.
Besides,when ACM enabled,windows can display both P3 and srgb content without extra gamut clamp.

[digiw]

I found this tool：dwm_lut

https://github.com/lauralex/dwm_lut/releases

The 3dlut profile can be loaded.

But it may not be fully compatible with win11 24h2. I am still looking forward to the update from the author of novideo srgb. This is the best choice for nvidia users!

[EianAtDawn]

Actually, this setting for me has the same effect as clamping to SRGB from within NoVideoSRGB!
Clamp gets disabled once you open NoVideoSRGB though so you have to toggle off and on again on windows while NoVideoSRGB is not running.
So atm I'm using NoVideoSRGB to set the clamp for just my second no HDR monitor and seems to be working fine..
Needs a bit more testing and keeping an eye on every update, but seems like Microsoft finally decided to implement an SRGB clamp as well..

Using an LG 32GP850 monitor on Nvidia Asus 4070 TUF..

[casef]

Actually, this setting for me has the same effect as clamping to SRGB from within NoVideoSRGB!

That's (part of) the intended point of ACM, yes.

[hwfanatic]

It also enables temporal dithering, by the way.

[markandgo]

It seems that ACM clamps my color from wide gamut to srgb. I am pairing ACM with my monitor profile I made from calibrating and everything looks correct. Does it make this tool obsolete?

[Cynersi]

i’ve had issues from friends who have their monitor brightness screwed up after upgrading to 24H2 on nvidia unless they disable this setting. has anyone noticed if this also clamps the gamma?

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On Thu, Nov 28, 2024 at 2:09 AM Minh Ngo ***@***.***> wrote: It seems that ACM clamps my color from wide gamut to srgb. Does it make this tool obsolete? — Reply to this email directly, view it on GitHub <#100 (comment)>, or unsubscribe <https://github.com/notifications/unsubscribe-auth/AKW2QHXRJ2GQZBPHXUDW6KT2C26R3AVCNFSM6AAAAABOVFCZ6SVHI2DSMVQWIX3LMV43OSLTON2WKQ3PNVWWK3TUHMZDKMBVGQYDCMRZGA> . You are receiving this because you authored the thread.Message ID: ***@***.***>

[Xgaming316]

Screwed up in what way? I'm not really sure yet if ACM accounts for EDID gamma, but even if it did it shouldn't be making a dramatic difference in brightness. Relatively raised blacks may make sense but I'm not sure of the scale you are talking about. It could also be a good idea to check that the color settings are set to default in both the monitor and computer (software/drivers). A good way to check is to use EDID novideo and compare that to ACM. If it's the same it's probably a settings issue and if they are different that might be a difference in what ACM is doing.

[Xgaming316]

It seems that ACM clamps my color from wide gamut to srgb. I am pairing ACM with my monitor profile I made from calibrating and everything looks correct. Does it make this tool obsolete?

ACM still doesn't have the option to choose between tone curves and, for certain situations, others may want to target different gamuts. It also doesn't support untagged ICCs and certain ICC features. Somewhat annoyingly, it doesn't support gamma so you can't easily target the assumed srgb tone curve or any other. For me though, unlocking 8+ bit depths significantly reducing banding is huge, which is why I'm trying to make things work despite some of the trade-offs.

[george-2022]

well tool doesn't work in windows 26120 build when i enabled 10bit in nvidia control panel + Color Management:

but working fine if you disable color management and just keep only 10bit :

DWM_LUT v4.0.2 also working in windows 11 26120 build, but if you use old nvidia drivers with WDDM 3.1 support, for example 552.44, with latest drivers just black screen and 3dlut doesnt't work and tool stays inactive, so probably tool author needs to add WDDM 3.2 support, probably it also has some bugs also, at least i found few bugs, but madvr 3dlut working fine, almost identical result as madvr DCI-P3 color profile in calibration settings