The development of new photoswitchable contrast agents requires analysis with both NMR and MRI. In this work a combined probe head for in situ light exposure is presented which can be used on NMR and MRI systems with both 7 Tesla. A probe head with four slanted quartz rods was fabricated. A dual tuned (1H and 2H) Helmholtz coil was integrated into the probe head. NMR and MRI experiments were performed on photoswitchable solutions (e.g. contrast agents). Results show that photoswitchable solutions can be successfully switched in situ and simultaneously analyzed with NMR or imaged with MRI.