Table-top Computed Lighting for Practical Digital Photography

Abstract

We apply simplified image-based lighting methods to reduce the equipment, cost, time, and specialized skills required for high-quality photographic lighting of desktop-sized static objects such as museum artifacts. We place the object and a computer-steered moving-head spotlight inside a simple foam-core enclosure, and use a camera to quickly record low-resolution photos as the light scans the box interior. Optimization guided by interactive user sketching selects a small set of frames whose weighted sum best matches the target image. The system then repeats the lighting used in each of these frames, and constructs a high resolution result from re-photographed basis images. Unlike previous image-based relighting efforts, our method requires only one light source, yet can achieve high resolution light positioning to avoid multiple sharp shadows. A reduced version uses only a hand-held light, and may be suitable for battery-powered, field photography equipment that fits in a backpack.