Comparison of the pixel values for extinction maps created with 2MASS and VISTA data (sensitivity limits: ~14.5 mag and ~19 mag, respectively). Each of the three panel groups shows a different magnitude limit. The leftmost plot shows a comparison for extinction maps where all source brighter than 14.5 mag in K_S are used. The panel in the centre and to the right display the same comparison, but with sources brighter than 16.5 and 18.5 mag in K_S, respectively. While the bottom figures directly compare the two measures, we plot their difference () at the top of each group. The orange lines represent 1:1 correlations between the parameters.