Increase in visual brightness plotted in 3D

The increase in visual brightness becomes very clear in this animated surface plot. In this animation, the brightness of image pixels seen by OSIRIS is plotted 'three-dimensionally', i.e. the brighter they are, the higher they are in the plot.
Images were taken at five-minute intervals around the impact time of 07:52 CEST (05:52 GMT/UT) on 4 July 2005.