Rest-frame B-band Tully-Fisher diagram, showing a comparison between our sample of 124 disk galaxies at a median redshift ⟨ z ⟩ ≈ 0.5 (solid symbols) and the local Tully-Fisher relation as given by Tully et al. (1998; the black dashed line indicates the fit to the local data (not shown in this figure); the dotted lines give the local 3σ scatter). The blue solid line shows the fit to the distant sample (with the slope fixed to the local value), which is offset from the local Tully-Fisher relation toward higher luminosities by ⟨ ΔM_B ⟩ = −0.47 ± 0.16 mag.