UE4 – Technical model visualization tips

Software:
Unreal Engine 4.25

This post is a summary of the tips given by Epic Games technical-artist Min Oh in his GDC 2017 lecture about improving photo-realism in product visualization, more specifically, how to render high quality surfaces.
I recommend watching the full lecture:

1. Render sharper reflections by increasing the Cubemap resolution of reflection captures:
   Project Settings > Engine > Rendering > Reflection > Reflection Capture Resolution
   * use powers of 2 values i.e. 256, 512, 1024….
   
2. Improve the accuracy of environment lighting by increasing the Cubemap resolution of the Skylight:
   * use powers of 2 values i.e. 256, 512, 1024….
   
3. Improve screen space effects accuracy like screen space reflections by setting the engine to compute high precision normals for the GBuffer:
   Set Project Settings > Engine > Rendering > Optimizations > GBuffer Format to:
   High Precision Normals
   
4. Use a high degree of tessellation (subdivision) for the models pre-import.
   Simpy put:
   Use high quality models.
5. Improve the surfaces tangent space accuracy, and as a result also the shading/reflection accuracy by setting the model’s static mesh components to encode high precision tangent basis:
   Static Mesh Editor > Details > LOD 0 > Build Settings > Use High Precision Tangent basis
   
6. Creating materials with rich dual specular layers by enabling material clear coat separate normal input:
   Project Settings > Engine > Rendering > Materials > Clear Coat Enable Second Normal
   Set the material Shading Model to Clear Coat and use a ClearCoatBottomNormal input node to add a normal map for the underlying layer:
   

Related:

1. UE4 – Lighting calculation tips
2. UE4 HDRI lighting
3. UE4 – Enable DXR ray-traced reflections