The mechanism of how lateral forces can produce artifacts in topographical images obtained by scanning force microscopy is analyzed theoretically. It is shown that due to the detailed elastic behavior of the force sensing cantilever, a scanning force microscope based on the light beam deflection method is particularly subject to such artifacts. They are produced by lateral forces, arising not only from friction but also from the topography itself Consequently, the images are modified by a self-distortion of the topography. The various effects contributing to the image contrast are demonstrated experimentally by images of a tribologically heterogeneous sample. The topographical contrast is compared with lateral force images. A quantitative analysis shows that both friction-induced and topography-induced topographical artifacts can be described reasonably well by the theoretical formulas.