Reabsorption of spontaneously emitted photons by optically active ions in a laser material can significantly affect the measured emission spectra. A measurement technique to suppress reabsorpion artifacts in fluorescence spectra is reported. A theoretical description of the method as well as experimental results are presented. In combination with another version of the pinhole method for the determination of reabsorption-free fluorescence lifetimes, this technique allows one to suppress the influence of reabsorption artifacts in emission cross sections calculated by the Füchtbauer–Ladenburg equation.