Color appearance of surfaces viewed through fog.

How do the colors of surfaces seen through fog depend on the chromatic properties of the fog? Prior work (e.g. Chen and D'Zmura, 1998 Perception 27 595-608) shows that the colors of surfaces seen through a transparent filter can be described by a convergence model. The convergence model takes into account color shift and change in contrast. Whether the convergence model can also be applied to fog was tested experimentally with an asymmetric matching task. In computer graphic simulation, observers adjusted the color of a surface seen through fog in order to match the color of a surface seen in the absence of fog. The convergence model fits the data well. The results suggest that the color constancy revealed in this task with fog is described best by a model that takes into account both shift in color and change in contrast.