Material brightness uniformity required

UE 4.15.0 - I have multiple static mesh panels with the same material, but the brightness is not uniform. How do I correct this?

This is a lightmap issue. Make your wall a single mesh instead of multiple.

Thanks @Raildex_ - but then, if I make the entire wall from one mesh, the door opening is streeeetched all crazy wide. I’m a noob… Is there a way to make a wall wider without stretching it? Or don’t think that way?
I think you’ll say, use a blank wall, stretch it, then ‘subtract’ the space for a door? Is that the way to do it?

Generally with lightmass it’s good to avoid having flat surfaces meeting up to form a larger flat surface. Try having the pieces end with a pillar, post, support beam, or intentional seam.

As previously mentioned this is a lightmap issue. You might find this resource on the topic useful. =)