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Layer systems for optical Bragg reflectors (grown by molecular beam epitaxy) were studied using double crystal topography and diffractometry. The initiation of stress relaxation was detected topographically in the substrate reflection and in different satellite reflections for undoped and slightly silicon doped layers (up to a doping level of 3×1017 cm-3). Higher silicon doping (1018 cm-3) prevented misfit dislocations. When using Czochralsky substrates it was observed that half‐loops were formed by misfit dislocations between pairs of threading dislocations. Misfit dislocations were shown to be situated on different levels of the layer stack. Satellite reflection topography is suggested as a new tool for directly observing strains in multilayer systems since the signal originates in the layer stack. Even for very small layer thicknesses good defect contrasts can be expected for high‐quality layers, as shown by simulations.