Fourier transform of the data. Top: one dimensional horizontal slice from a 2D Fourier transform of the images presented in Fig. 8. For the Schwarzschild metric, the image was decomposed into the primary image (smooth ring, dashed blue) and sharp secondary ring (dashed red). For very long baselines (large spatial frequencies) the secondary ring dominates the total emission. Bottom: similar, but for the images shown in Fig. 10. While the boson-star image does not exhibit a secondary ring, the amplitude falloff is similar to that of the Kerr spacetime.