I tested this on a Mac Pro in UE 4.15, 4.16, 4.17, and 4.18. As a possible workaround for the fog issue, I've discovered that setting Atmospheric Fog > Lighting > Disable Ground Scatter to "True" will prevent the fog from rendering black in editor. 

Per Licensee: 

I got some issues with my translucent materials on MacOs devices, this issues appears on packaged builds and sometimes in Play In Editor (But usually, in PIE works fine, except the atmospheric fog that is always black without opacity).

The translucent area appears to be black or pink, depend on the level that I'm on, also, it happens the same thing with the Atmospheric fog of Unreal

I tried changing the r.TranslucencyLightingVolumeDim (that solved some similar issues on PS4 builds) but without any luck

That happens with all my translucent materials and particles

Steps to Reproduce
  1. Download [sample project|[Link Removed]]
  2. Open project on a Mac device
  3. Play in Editor to see Atmospheric Fog shows up black
  4. Play in Standalone mode to see mesh with blue translucent material renders black (Shape_Plane8)


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ComponentUE - Graphics Features
Affects Versions4.
Target Fix4.20
Fix Commit3831616
Main Commit3856245
Release Commit3831616
CreatedJan 3, 2018
ResolvedJan 11, 2018
UpdatedJan 17, 2019
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