Microscopy system for observing fluorescence from different fluorescent dyes in an object plane, wherein the microscopy system comprises an illumination system for illuminating the object plane with illumination radiation and an observation system for simultaneously providing a first and second observation beam path (32, 33) for optical imaging of the object plane, wherein the illumination system comprises a first operating state, in which the illumination radiation has a spectrum which comprises a first excitation band of a first fluorescent dye and simultaneously is partly free from a second excitation band of a second fluorescent dye which is different from the first fluorescent dye, and the illumination system comprises at least a second operating state, in which the illumination radiation has a spectrum which comprises the second excitation band of the second fluorescent dye, wherein the observation system comprises a first operating state, in which observation radiation routed in the first observation beam path in sections has a spectrum which comprises a first fluorescence band of the first fluorescent dye, and wherein the observation system comprises at least one camera, wherein the camera is supplied by the observation radiation routed in the first observation beam path, wherein the microscopy system is a stereo microscopy system, in which the first observation beam path includes a first angle (□) with an optical axis of the microscopy system and the second observation beam path includes a second angle (-□) with the optical axis of the microscopy system, wherein the first angle (□) and the second angle (-□) have the same magnitude, wherein, in at least one operating state of the illumination system, an illumination filter carried by an illumination filter carrier is arranged in an illumination beam path provided by the illumination system, which illumination filter is transmissive to the excitation band (A1, A2) of a fluorescent dye to be observed and simultaneously substantially non-transmissive to the excitation band (A2, A1) of a different fluorescent dye, and the illumination system comprises a lamp which emits white light, characterized in that the observation system comprises at least a second operating state, in which observation radiation routed in the first observation beam path in sections has a spectrum which is partly free from the first fluorescence band of the first fluorescent dye, in that a first observation filter carrier is arranged in the first observation beam path of the observation system, which first observation filter carrier carries a first observation filter and is switchable between at least a first and a second operating state, in that a second observation filter carrier is arranged in the second observation beam path of the observation system, which second observation filter carrier carries at least one further observation filter (61', 62') and is switchable between at least a first and a second operating state, in that the first observation filter carrier furthermore carries an infrared band elimination filter, wherein, in the second operating state of the first observation filter carrier, the observation radiation routed by the first observation beam path can be supplied to the camera via the infrared band elimination filter, and in that the microscopy system furthermore comprises a control device, wherein the control device is configured to selectively switch both the illumination system and the observation system and thus the first and second observation filter carriers (60, 60) into the first operating state or switch both the illumination system and the observation system and thus the first and second observation filter carriers (60, 60) into the second operating state, such that, in the first operating state, an observation of fluorescence radiation is facilitated by the observation beam paths (32, 33) and, in the second operating state, an observation under white light is facilitated by the first observation beam path and an observation of fluorescence is facilitated in the second observation beam path.