Many-beam dynamical simulations and observations have been made for large-angle convergent-beam electron diffraction (LACBED) imaging of crystal defects, such as stacking faults and dislocations. The simulations are based on a general matrix formulation of dynamical electron diffraction theory by Peng and Whelan, and the results are compared with experimental LACBED images of stacking faults and dislocations of Si angle crystals. Excellent agreement is achieved.