Certain fluorophores, in particular those that can undergo photoinduced radical pair reactions are known to exhibit a magnetic field dependent fluorescence summarized in the term magnetic field effect (MFE). We tried to reproduce experiments that reported magnetic field enhanced fluorescence for commonly used organic dyes with a high quantum yield suitable for single molecule localization microscopy. We find that the enhanced fluorescence is due to fluorescence reflected by the magnet's surface rather than MFE.
