Plasma regions with an enhanced light emission are easily found in dusty plasmas. They can appear during some instabilities induced by the presence of a high dust particle density, or in the plasma center. In this last case, this region is called the "void" and corresponds to a dust-free region. In this paper, experimental characterizations of these two types of regions are presented. Experiments are performed in the PKE-Nefedov reactor where Ar or Kr plasmas are produced by a capacitively-coupled rf discharge with a typical power of about 3 W at a pressure around 1.6 mbar. Dust particles are grown by sputtering a polymer layer previously deposited on the electrodes.