Oh man, I just picture myself cursing because the renderings are always too dark... [:-/]

I turned off some lights to show the influence of IBL rendering on the horizon line with a uniform background (part of the sky and ground of the same color).


I do not think that with a half-sphere and light panels I would get this desired atmosphere in the first 4 images. Unless the inside of the half-sphere emits light as for the sky.