  We study the effect of inhomogeneities on light propagation. The Sachs
equations are solved numerically in the Swiss-Cheese models with
inhomogeneities modelled by the Lemaitre-Tolman solutions. Our results imply
that, within the models we study, inhomogeneities may partially mimic the
accelerated expansion of the Universe provided the light propagates through
regions with lower than the average density. The effect of inhomogeneities is
small and full randomization of the photons' trajectories reduces it to an
insignificant level.
