  By varying the absorption coefficient and width of an intralipid- India ink
solution in a quasi one-dimensional experiment, the transition between the
ballistic and the diffusive regimes is investigated. The medium's attenuation
coefficient changes abruptly between two different values within a single
mean-free-path. This problem is analyzed both experimentally and theoretically,
and it is demonstrated that the transition location depends on the scattering
coefficient as well as on the measuring solid angle.
