Disable contrast enhancement on SP4

[AlexPermit]

How do I disable contrast enhancement, sometimes called adaptive contrast enhancement, on the surface pro 4? If I could install the Intel Iris Graphics Control Panel, this setting would be under Video->Image Enhancement->Advanced->Contrast Enhancement.

I could probably force an install of the Intel Iris Graphics Control Panel by following the intstructions on this tread: Graphics control panel/ colour management | Microsoft Surface Forums. But I would prefer not to, since the intel driver seems to chew up background cpu.

If I had a surface pro 3, I could use Goodbytes Surface Tweak Tool: Nv GPU Pro - Surface Tweak Tool. But it doesn't seem to support a surface pro 4.

I experimented with my intel nuc (which does have the iris control panel installed) and discovered two registry keys changed when enabling contrast enhancement. They were:

1. \\HKLM\Software\Intel\Display\igfxcui\MediaKeys\EnableACE : changed FROM 0x0 TO 0x1
2. \\HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\MMDevices\Audio\Render\{952056c7-63d1-436b-be30-0562ee3143c3}\Properties: FROM 41 00 00 00 01 00 00 00 02 4E 11 C2 02 4E 11 C2 TO 41 00 00 07 01 00 00 00 02 4E 11 C2 02 4E 11 C2

The surface pro 4 has a registry entry similar to the first: \HKLM\Software\Intel\Display\igfxcui\Media\EnableACE. I tried setting it to 0x0, but it appears to have no no effect.

Help!

 

[rquellet]

How do I disable contrast enhancement, sometimes called adaptive contrast enhancement, on the surface pro 4? If I could install the Intel Iris Graphics Control Panel, this setting would be under Video->Image Enhancement->Advanced->Contrast Enhancement.

I could probably force an install of the Intel Iris Graphics Control Panel by following the intstructions on this tread: Graphics control panel/ colour management | Microsoft Surface Forums. But I would prefer not to, since the intel driver seems to chew up background cpu.

If I had a surface pro 3, I could use Goodbytes Surface Tweak Tool: Nv GPU Pro - Surface Tweak Tool. But it doesn't seem to support a surface pro 4.

I experimented with my intel nuc (which does have the iris control panel installed) and discovered two registry keys changed when enabling contrast enhancement. They were:

1. \\HKLM\Software\Intel\Display\igfxcui\MediaKeys\EnableACE : changed FROM 0x0 TO 0x1
2. \\HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\MMDevices\Audio\Render\{952056c7-63d1-436b-be30-0562ee3143c3}\Properties: FROM 41 00 00 00 01 00 00 00 02 4E 11 C2 02 4E 11 C2 TO 41 00 00 07 01 00 00 00 02 4E 11 C2 02 4E 11 C2

The surface pro 4 has a registry entry similar to the first: \HKLM\Software\Intel\Display\igfxcui\Media\EnableACE. I tried setting it to 0x0, but it appears to have no no effect.

Help!

Interesting find. I set \HKLM\Software\Intel\Display\igfxcui\Media\EnableACE and the entry next to it to 0x0. It might have worked. Do you have a test case to see if the contrast is changing? I tried setting my display background to black, then switched to battery power, then I moved a white webpage across the screen. I didn't see any backlight or contrast changes.

I also used this gradient to test for banding that results from contrast compression:
https://www.drycreekphoto.com/images/calibration/graygradient.png
I didn't see any banding when switching to battery power.

I don't feel like reverting the registry settings to default to see if my tests pass or fail with default settings, but maybe someone else can. Edit: I'm noticing the display dim and brighten based on screen content now. Easier to see with screen set to 10% brightness.

Last, maybe we can ask GoodBytes what settings he changes with the Surface Tweak Tool.

 

[AlexPermit]

My test case is a third party app that displays video and flickers when enhanced contrast in enabled. I know, its not a very controlled test. But its the only one I know of.

Good idea on asking Goodbytes. Would you like to ask or shall I?

 

[rquellet]

My test case is a third party app that displays video and flickers when enhanced contrast in enabled. I know, its not a very controlled test. But its the only one I know of.

Good idea on asking Goodbytes. Would you like to ask or shall I?

Please do if you'd like.