# Empty scene is not absolutely black on iOS

**URL:** <https://forums.unrealengine.com/t/empty-scene-is-not-absolutely-black-on-ios/428715>\
**Category:** Mobile\
**Tags:** unreal-engine, iOS, Tonemapping, question\
**Created:** [July 4, 2018, 7:54pm UTC](https://forums.unrealengine.com/t/empty-scene-is-not-absolutely-black-on-ios/428715 "2018-07-04T19:54:24Z")\
**Posts on this page:** 3\
**Page:** 1

<div class="post-metadata">

**Author:** ![RenovatioNova](https://d3kjluh73b9h9o.cloudfront.net/original/4X/2/8/5/28502927f1d97ba1051b3b47ccfe17233bf41ef0.png) [@RenovatioNova](https://forums.unrealengine.com/u/RenovatioNova)\
**Post date:** [July 4, 2018, 7:54pm UTC](https://forums.unrealengine.com/t/empty-scene-is-not-absolutely-black-on-ios/428715/1 "2018-07-04T19:54:24Z")

</div>

I open an empty scene on iPhone X and see, that it is not as dark as an absolute dark. It is a little bit grey, just a bit. You can notice it because the camera offset on top of the phone becomes visible. I have next device profile:

```
[IOS DeviceProfile]
DeviceType=IOS
BaseProfileName=
+CVars=r.MobileContentScaleFactor=0
+CVars=r.DefaultFeature.Bloom=True
+CVars=r.DefaultFeature.AmbientOcclusionStaticFraction=False
+CVars=r.BloomQuality=4
+CVars=r.DepthOfFieldQuality=1
+CVars=r.LightShaftQuality=1
+CVars=r.RefractionQuality=1
+CVars=r.ShadowQuality=2
+CVars=r.HZBOcclusion=0
+CVars=r.EarlyZPass=0
+CVars=r.EarlyZPassMovable=0
+CVars=r.TranslucentLightingVolume=0
+CVars=r.AllowPointLightCubemapShadows=0
+CVars=r.PostProcessAAQuality=6
+CVars=r.MobileMSAA=4
+CVars=r.Decal.StencilSizeThreshold=-1
+CVars=r.MetalVertexParameterSize=50
+CVars=r.MetalPixelParameterSize=50
+CVars=slate.AbsoluteIndices=1
+CVars=r.MorphTarget.Mode=0
```

---

<div class="post-metadata">

**Author:** ![ufna](https://d1ap1mz92jnks1.cloudfront.net/user_avatar/forums.unrealengine.com/ufna/32/1194675_2.png) [@ufna](https://forums.unrealengine.com/u/ufna)\
**Post date:** [July 5, 2018, 6:49am UTC](https://forums.unrealengine.com/t/empty-scene-is-not-absolutely-black-on-ios/428715/2 "2018-07-05T06:49:36Z")

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I suppose that’s because of USE\_MSAA define block, which should be disabled for Metal:

```
	#if USE_MSAA
		// Do after jitter for grain as an optimization.
		SceneColor.rgb *= rcp(SceneColor.r*(-0.299) + SceneColor.g*(-0.587) + SceneColor.b*(-0.114) + 1.0);
		// Try to kill negatives and NaNs here
		SceneColor.rgb = max(SceneColor.rgb, 0);
	#endif
```

---

<div class="post-metadata">

**Author:** ![RenovatioNova](https://d3kjluh73b9h9o.cloudfront.net/original/4X/2/8/5/28502927f1d97ba1051b3b47ccfe17233bf41ef0.png) [@RenovatioNova](https://forums.unrealengine.com/u/RenovatioNova)\
**Post date:** [July 5, 2018, 11:21am UTC](https://forums.unrealengine.com/t/empty-scene-is-not-absolutely-black-on-ios/428715/3 "2018-07-05T11:21:47Z")

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Problem was in tonemapper. For 4.19 I used next config to solve this problem:

```
+CVars=r.TonemapperFilm=0
+CVars=r.Mobile.TonemapperFilm=1

```

Property **r.Mobile.TonemapperFilm=1** is the most important in this problem.