Fig. 5.

Position-dependent beam hardening evaluation. SPR deviations for the CaCO₃ 50% insert (a, c, e) and HE Cortical Bone insert (b, d, f). The inserts were placed at different distances from the centre in the ME phantom with a diameter of 20 cm (a, b), 30 cm (c, d), and 40 cm (e, f). The numbers on the x-axes correspond to the insert positions as shown in Fig. 1 and Supplementary Fig. S1. The mean difference and its standard deviation over all voxels are shown.