foliage half bright, half dark

I imported outside foliage mesh and build my own very simple material in UE. The foliage appear fine in material editor, but in the scene they show half bright-half dark, (seem dark in the middle of the tree and bright on the outside part) I’m not sure if this is related to material, or lighting?

Your problem is in the “specular” input for the foliage material. It’s set to 0. If you didn’t know, the specularity of a material is (oversimplified) how non-metallic surfaces reflect light. It looks black because the low specular levels tell the surface to absorb light, not reflect it. Try a value of 0.5 and see how that feels.

Let me know if that helps. If not, I’ll take another shot.