Control system and method for determining illumination intensity in fluorescence microscope and corresponding microscope system

The invention relates to a control system for automatically determining the illumination intensity of a light source of a fluorescence microscope, the light source for stimulating a fluorophore in a sample and being configured to vary the illumination intensity, the microscope having a detector for detecting an image intensity of the sample, the control system being configured to determine the illumination intensity of the light source after a change in the light path. A control value for the illumination intensity of the light source is automatically determined in order to achieve a desired value of an inspection parameter characterizing the sample inspection, wherein determining the control value of the illumination intensity of the light source is based on a value of the illumination intensity set before the change in the light path, based on a value of an inspection parameter used before the change in the light path, and based on a physical model in the light path, the physical model maps the illumination