The free-form light stage

Abstract

The Free-form Light Stage captures the reflectance field of an object using a freely movable, hand-held light source. By photographing the object under different illumination conditions, we are able to render the object under any lighting condition, using a linear combination of basis images. Our technique builds on recent techniques, such as the Light Stage [Debevec et al. 2000], where light sources are placed at fixed and known positions (e.g. using a gantry). We remove this limitation, and put no restrictions on light source placement.