Photon correlation spectroscopy on time scales down to a nanosecond and below is a powerful method for probing the dynamics of free-standing liquid crystal films. The technique takes advantage of the high reflectivity of these films to obtain significant count rates even for very high frequency motions of the film. Following previous work [DOI: 10.1103/PhysRevLett.94.067801] on relatively thin smectic films, where the dominant scattering at optical wavevectors comes from the underdamped, fundamental undulation mode, we have focused on overdamped motion in thick films, where both higher order modes involving layer compression and very high frequency, nonhydrodynamic director tilt fluctuations contribute significantly. In common cyanobiphenyls, we show how the layer sliding viscosity, layer compression elastic constant, and relaxation rate for tilt fluctuations can be separately extracted from the measured dispersion of the film dynamics. We will also report on application of the technique to the conventional smectic-A to C phase transition and to the chiral smectic-A to CĄ transition. Finally, we will present preliminary results obtained on magnetically-aligned films formed from liquid crystal gels.