Geometric albedo ω_disk of HD 100546 in the different filters. The geometric albedo is a measure of the fraction of light scattered by the disk (see Eq. (3)) and text for definition). Displayed are both observations (diamonds with systematic and measurement errors) and the same models as Fig. 5: A large, intermediate and small grain (red, gray, and blue solid line respectively). A model with intermediate-sized grains with an albedo close to one is also displayed (gray dotted line).