The elastic scattering cross sections for the reactions Cd-110,Cd-116(alpha, alpha)Cd-110,Cd-116 at energies above and below the Coulomb barrier are measured to provide a sensitive test for the alpha-nucleus optical potential parameter sets. The potentials under study are a basic prerequisite for the prediction of alpha-induced reaction cross sections, e. g. for the calculation of stellar reaction rates in the astrophysical p- or gamma-process. Moreover, the variation of the elastic alpha scattering cross sections along the Z = 48 isotopic and N = 62 isotonic chain is investigated by the study of the ratios of the of Cd-110,Cd-116(alpha, alpha)Cd-110,Cd-116 scattering cross sections at E-c.m. approximate to 15.6 and 18.8 MeV and the ratio of the Cd-110(alpha, alpha) Cd-110 and Sn-112(alpha, alpha)Sn-112 reaction cross sections at E-c.m. approximate to 18.8 MeV, respectively. These ratios are sensitive probes for the alpha-nucleus optical potential parameterizations.