  First results of multi-wavelength measurements of the twilight sky background
using all-sky camera with RGB-color CCD conducted in spring and summer of 2016
in central Russia (55.2 deg N, 37.5 deg E) are discussed. They show the effect
of aerosol scattering at altitudes up to 35 km which significantly increases to
the long-wave range (624 nm, R channel). Analysis of sky color behavior during
the light period of twilight with account of ozone Chappuis absorption allows
retrieving the angle dependencies of scattering on the stratospheric aerosol
particles. This is used to find the parameters of lognormal size distribution:
median radius about 0.08 microns and width 1.5-1.6 for stratospheric altitude
range.
