Abstract: We report nonstationary photorefractive holograms in absorbing Bi12TiO20 samples with different degrees of hole-electron competition exhibiting resonance peaks due to electron and hole charge carriers. One sample with moderate hole-electron competition and another with a much larger effect were studied. Experimental data from these samples were analyzed using a theoretical model accounting for electrical hole-electron coupling, wave coupling, and response-time variation along the sample thickness due to bulk light absorption. Comparing experimental data and theoretical results allows finding out material parameters adequately describing hole and electron photoactive centers in these samples Ver menos