Fitted solar third signature as seen in Fig. 4 (red) that does not take the wavelength dependence into account and the revised model (black shaded) that does. Individual lines are color coded according to their wavelength. The lower boundary corresponds to a wavelength of 400 nm and the upper to 750 nm, covering the spectral range of the data. The individual lines’ measurements (blue) are shown without their error bars for visibility reasons. The revised model muchbetter captures the spread toward deeper lines.