The determination of resonance properties is a long standing challenge. Magnetic moments of resonances are a valuable testing ground for baryon structure calculations. We have shown in a former experiment that the extraction of the Delta(+)(1232) magnetic dipole moment is feasible via the measurement and analysis of the reaction gamma p --> pi(0)gamma'p, in which the photon gamma' carries the desired information. Such an experiment has been repeated with high precision using the Crystal Ball and TAPS detectors at the MAMI accelerator facility. Preliminary results will be presented. Furthermore, the perspectives for accessing the magnetic moment of the S-11 (1535) resonance in radiative eta photoproduction gamma p --> eta gamma'p will be discussed.