[en] Intrinsic (WO₄)^3- centers can be created in lead tungstate by irradiation with light having energies well below the bandgap, i.e. the threshold for excitation of the blue tungstate luminescence. Detailed photo-ESR studies show that this happens by ionization of defect states in the bandgap which have been prefilled by suitable radiation. Depending on the energy depth of the respective defects a wavelength between near-infrared and near-UV is necessary for the ionization process. A simultaneous production of different electron centers is observed via participation of the conduction band. This allows an easy determination of the trap level energies