The dynamic mode of scanning electron microscopy (SEM) cathodoluminescence (CL) based on computer-aided acquisition and fast processing of image data is introduced as a unique method to reveal glide dislocations as extended mobile recombination centres in several III/V and II/VI semiconductors with zincblende and wurtzite lattice structure respectively. Local plastic deformation by in situ scratching or indentation at low-index sample surfaces is shown to be easily used to generate and propagate individual single dislocations of various types. Dislocation dynamics and defect-related recombination activity, as simultaneously observed at separatemoving dislocation segments having screw- or edge-type structure, are considered by analysing the CL movies taken. Our results give evidence of a complex relationship between dynamic and recombination active defect properties depending on the structure of the dislocation and the material studied. In particular, polar A(g) and B(g) dislocations are clearly different in respect of both their dynamics and recombination active behaviour, as discussed for fresh glide dislocations in ZnO and GaAs samples. ? Institute of Physics Publishing