Fig. 1

Undeformed torus seen from an inclination of 45° (left) and 85° (right). The color bar, common to both panels, shows the ratio Δ ≡ (νobs/νem)3, where νobs and νem are the observed and emitted frequencies. This is the redshift factor that modulates the observed intensity. At high inclination, the beaming effect (which makes the redshift factor brighter on the approaching side of the torus) is more pronounced and the apparent area of the secondary image is bigger.
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