Intervening Ni II absorption towards the quasar LBQS 2206–1958 at z_a ≈ 1.92. The opacity profiles for the 1317 (thin black line), 1370 (red), 1703 (green), 1709 (blue), 1741 (thick black), and 1751 Å (cyan) transitions are shown in the upper panel. The ratio of any given profile to the 1741 Å profile is shown in the lower panel. The ratios are better defined at velocities for which the opacity is large; they range from 0.125 (for 1703 Å) up to 1.43 (1370 Å), thus covering a dynamical range of 11.4. At v_helio = 0 km s⁻¹, the redshift is z_a = 1.9200.