With a ring dye laser persistent spectral hole-burning was measured by fluorescence excitation spectroscopy in the zero-phonon lines of the2llg↔2llutransition in KI:S2−and of the3H4→3P0transition of a defect center with three D−ions in SrF2:Pr3+:D−and also in the zero-phonon line at 462.5 nm of a color center in neutron-irradiated and annealed α-Al2O3. In all three lines holes with a width in the order of 1 GHz could be obtained at 1.5 K with single frequency laser. With broad-band laser in KI:S2−and SrF2:Pr3+:D−spectral redistribution within the full range of inhomogeneous broadening could be observed which are explained by a photophysical model based on barrier crossing in asymmetric double-well-potentials. In the case of sapphire a photobleaching process is dominant which is effective also for nonselective excitation, and the holes are thermoresistant up to 300 K.