It's a bit of both, i'm useing Archers Bi Skymod which does give the daylight a bit of an eerie feel, and i do darken the skins quite a bit, we haven't totally decided on whether to use the skymod but in general it does look better than vannila lighting, though not as good as the Rtw skymod. Grading the units is something i intend to look at when the mod is finished as it's much easier to grade the whole lot in one go using a photoshop actions.