1. A surgical lamp comprising: a light source; a camera; at least one first polarization filter that is rotatable, the at least one first polarization filter to receive excitation light that is reflected from a surgical site and non-polarized light caused by fluorescence by the excitation light at the surgical site; a filter positioned in front of a light entrance of the camera and configured to allow light having a defined wavelength range to pass through the filter, the defined wavelength range including wavelengths of the excitation light and the fluorescence light; an electronic evaluation unit connected to the camera, the electronic evaluation unit being configured to evaluate the image brightness of an image captured by the camera; and a control unit connected to the at least one first polarization filter and to the electronic evaluation unit, the control unit being configured to rotate the at least one first polarization filter based on an evaluation by the electronic evaluation unit of the image captured by the camera.