  We have investigated scintillation light distribution in BaF$_{2}$ and pure
CsI crystals with dimensions 3x3x20 cm$^{3}$ using the Geant4 toolkit. The
diffuse wrapping material is selected as coating for the crystals. The
simulated cosmic muons and 105 MeV electrons are used as beam particles. The
optical attenuation along the crystals is explored with the simulation data. We
have demonstrated the impact of the crystal surface finish on the light
distribution at the crystal end, optical photon arrival time, incidence angle
distributions, and optical attenuation for the studied crystals.
