Reddening correction computed for each star depending on its line-of-sight distance, as a function of its distance from the Galactic plane Z. The grey-scale colours represent the star counts in log ₁₀(N). The contour lines contain 33%, 66%, 90% , and 99% of the stars. As expected the corrections made to E(B − V)_a are only for the stars located closer than 400 pc from the Galactic plane.