Photon-conservation diagnostics for the two resonant Fe ii transitions, λ2374 UV2 (bottom) and λ2600 UV1 (top), with only one Fe ii* re-emission channel (Fe ii*λ2396 and Fe ii*λ2626 respectively). In both panels, the x-axis is the resonant absorption equivalent width, and the y-axis is the total re-emission equivalent width from the resonant and non-resonant transitions. However, resonant re-emission (emission infilling) is negligible for the Fe ii λ2374 transition (Tang et al. 2014; Zhu et al. 2015). The diagonal black line represents photon-conservation between emission and absorption processes. The solid colored points represent the Fe ii* emitters from this sample with the emission infilling correction (see text). The black lines associated with these points in the top panel trace the difference between the measured and corrected equivalent width values. The solid diamonds represent theoretical predictions from the radiative transfer models of Prochaska et al. (2011). Gray diamonds indicate isotropic outflow models, which all respect photon conservation, and the diamonds with colored outlines show variations to the geometry and dust content that decrease the total amount of re-emission.