TITLE: Multi-scale Data Visualization: Illumination and Perception Chris Weigle Joint Institute for Computational Sciences University of Tennessee and Oak Ridge National Labs ABSTRACT: Large datasets typically contain coarse features comprised of ï¬^Áner sub- features. Even if the shapes of the small-scale structures are evident in a 3D display, the aggregate shapes they suggest may not be easily inferred. From previous studies in visual perception, the evidence has not been clear whether physically-based illumination confers any advantage over local illumination for understanding scenes that arise in the visualization of large data sets. I present my recent research showing that physically-based illumination can improve the perception of static scenes of complex 3D geometry from flow fields. I performed two human-subjects experiments (a depth discrimination task and a shape discrimination task) to quantify the effect of physically-based illumination on task performance. I show that for the considered tasks physically-based illumination influences participant performance as strongly as perspective projection, suggesting that physically-based illumination is in fact a strong cue to the layout of complex data. BIO: Chris Weigle is a post-doctoral researcher with the University of Tennessee and Oak Ridge National Labs supported Joint Institute for Computational Sciences. His research includes perceptual and cognitive issues in scientific and medical visualization, with a particular interest in displays of large-scale or geometrically-complex data. Weigle received his Ph.D. in Computer Science from the University of North Carolina in 2006.