Updated test procedure
Witcher 3 GOTY, GOG, v. 1.31. Velen.
Birch trees with STLM 3.1.1, no ReShade : http://i.imgur.com/uVv0e6v.jpg
Birch trees Vanilla, no ReShade : http://i.imgur.com/dq66JsF.jpg
Birch trees with STLM 3.1.1, no ReShade : http://i.imgur.com/7oEZldQ.jpg
Birch trees Vanilla, no ReShade : http://i.imgur.com/ZIozi9y.jpg
Apple trees with STLM 3.1.1, no ReShade : http://i.imgur.com/gtJfEBb.jpg
Apple trees Vanilla, no ReShade : http://i.imgur.com/kNA9upm.jpg
Moon with STLM 3.1.1, ReShade : http://i.imgur.com/rZAgf8n.jpg
Moon Vanilla, ReShade : http://i.imgur.com/CB9LD1u.jpg
Lavender with STLM 3.1.1, ReShade : http://i.imgur.com/zDco663.jpg
Lavender Vanilla, ReShade : http://i.imgur.com/4DaXbAH.jpg
I can see a really big improvement in Ambient Occlusion, especially on the grass, with STLM 3
Witcher 3 GOTY, GOG, v. 1.31. Velen.
Birch trees with STLM 3.1.1, no ReShade : http://i.imgur.com/uVv0e6v.jpg
Birch trees Vanilla, no ReShade : http://i.imgur.com/dq66JsF.jpg
Birch trees with STLM 3.1.1, no ReShade : http://i.imgur.com/7oEZldQ.jpg
Birch trees Vanilla, no ReShade : http://i.imgur.com/ZIozi9y.jpg
Apple trees with STLM 3.1.1, no ReShade : http://i.imgur.com/gtJfEBb.jpg
Apple trees Vanilla, no ReShade : http://i.imgur.com/kNA9upm.jpg
Moon with STLM 3.1.1, ReShade : http://i.imgur.com/rZAgf8n.jpg
Moon Vanilla, ReShade : http://i.imgur.com/CB9LD1u.jpg
Lavender with STLM 3.1.1, ReShade : http://i.imgur.com/zDco663.jpg
Lavender Vanilla, ReShade : http://i.imgur.com/4DaXbAH.jpg
I can see a really big improvement in Ambient Occlusion, especially on the grass, with STLM 3