The basic features of scattering are shared by a number of closely related scatterer systems. The most elementary model for these systems is the random phase screen (RPS). In this article, predictions of the RPS theory are compared with the experimental data obtained by analysing scattered light speckle patterns from a film made of a semicrystalline polymer. On the basis of results obtained, it is possible (a) to classify speckle types depending on the illuminating conditions, (b) to measure speckle "smoothing" by determining the contrast of speckle intensity fluctuations, (c) to illustrate the relation between object and speckle movements in different geometries for simple types of sample movement (rotation, linear continuous translation and step-wise translation). The experimental data tend to confirm the validity of RPS theory in the case of polymer films. It is indicated that under certain conditions the statistical, temporal and spatial coherence properties of the scattered light are sensitive to the detailed internal structure of the scattering medium.