The present invention relates to an illuminating apparatus for an operating microscope comprising two observation beam paths (152, 154) for a first observer (main surgeon) and two observation beam paths (156, 158) for a second observer (assisting surgeon), comprising an illuminating system (102; 106a, 108a, 172) and deflecting means (118, 120, 170), for deflecting light emanating from the illumination system onto an object (200) that is to be observed, wherein the deflecting device comprises a first deflecting element (118) which is associated with a first observation beam path (152) of the first observer and a first observation beam path (156) of the second observer, and a second deflecting element (120) which is associated with a second observation beam path (154) of the first observer and a second observation beam path (158) of the second observer.