Yeah, I've had that too, but that's not the case here. For this particular piece (LM Stormguards outfit bought at DAZ) there's MAT presets, and like you can see the right side appears normal. Also it often, but not always, seems to be appearing on only one side. It's the same texture & bumpmap, so it must be Poser's renderer that treats on half of the texture/bump differently.