  The atmospheric scattering of light has a significant influence on results of
optical observations of air showers. It causes attenuation of direct light from
the shower, but also contributes a delayed signal to the observed light. The
scattering of light therefore should be accounted for, both in simulations of
air shower detection and reconstruction of observed events. In this work a
Monte Carlo simulation of multiple scattering of light has been used to
determine the contribution of the scattered light in observations of a point
source of light. Results of the simulations and a parameterization of the
angular distribution of the scattered light contribution to the observed signal
(the point spread function) are presented.
