We demonstrate a novel light probe which can estimate the full dynamic range of a scene with
multiple bright light sources. It places diffuse strips between mirrored spherical quadrants,
effectively co-locating diffuse and mirrored probes to record the full dynamic range of illumination
in a single exposure. From this image, we estimate the intensity of multiple saturated light sources
by solving a linear system.
Recording on-set illumination to render virtual objects into a real scene is often accomplished by
acquiring a panoramic, high-dynamic range (HDR) image where the object is to be inserted, and to use
this HDRI map as an image-based lighting source on the CG object. The spherical panorama can be obtained
by stitching HDR fisheye images from different directions, or more rapidly by photographing a mirrored
sphere. Shooting HDR is necessary to capture light sources - they typically exceed ambient light by
several orders of magnitude - but it requires recording, aligning, and assembling a range of exposures
which can be time-consuming and complicates dynamic capture. If there is just one bright light in the
scene, its intensity can be determined from an image of a diffuse gray ball, with the remaining illumination
imaged accurately in the mirrored sphere. Even so, two images are required, and only one saturated light
source is estimated. We relieve both restrictions.