We present photoluminescence studies onCdSxSe1−xsemiconductor doped glasses with gap energies ranging from about 2 to 3 eV (400–600 nm). The investigations were performed by near-resonance as well as temperature-dependent resonance Raman spectroscopy. On the basis of the strongly resonant behavior of the deep trap photoluminescence with the excitonic states of the nanocrystallites, we have demonstrated that—besides the effect of photodarkening—inconsistencies in the experimental results of semiconductor doped glasses presented in literature, could be due to changes in the electronic resonance conditions when experimental parameters are changed. ©1997 American Institute of Physics.