Stationary and dynamic properties of photo-induced light scattering (PILS) have beenstudied as a function of the photorefractive crystal thickness. A mono-exponential growthof the scattering amplification coefficient as well as a deceleration of the scatteringrecording dynamics is found with increasing crystal thickness. The experimental dataset is analyzed by considering scattering centers located (i) in the crystal bulkor (ii) near to the crystal surface. By comparing experimental and theoreticalresults we can conclude that the major contribution to the output scattering signaloriginates from a thin crystal region frontier to the surface of light incidence(near-surface). The deceleration of the scattering dynamics is interpreted as the resultof the competition between differently recorded noisy photorefractive gratings.