Logarithm of the ratio of the monochromatic cross sections for the stellar mixture with the new Ni data (κ_SR) and those with the OP Ni data (κ_OP) vs. u, and the same quantity for Ni alone (thick and thin solid lines, respectively, left scale). The dashed line shows the F(u) function (right scale). The dotted line represents a ratio of one. For the sake of legibility, the spectra have been convolved with a Gaussian kernel with a standard deviation of 0.05.