Element specific unoccupied electronic states of Cu In, Ga S2 were studied as a function of the In Ga ratio by combining X ray absorption spectroscopy with density functional theory calculations. The S absorption edge shifts with changing In Ga ratio as expected from the variation of the band gap. In contrast, the cation edge positions are largely independent of composition despite the changing band gap. This unexpected behavior is well reproduced by our calculations and originates from the dependence of the electronic states on the local atomic environment. The changing band gap arises from a changing spatial average of these localized states with changing alloy composition