This tutorial shows how image-based lighting can illuminate synthetic objects with measurements of real light, making objects appear as if they’re actually in a real-world scene.I mage-based lighting (IBL) is the process ofilluminating scenes and objects (real or syn- thetic) with images of light from the real world. Itevolved from the reflection-mapping technique 1,2 in which we use panoramic images astexture maps on computer graphicsmodels to show shiny objects reflect-ing real and synthetic environments.IBL is analogous to image-basedmodeling, in which we derive a 3Dscene’s geometric structure fromimages, and to image-based render-ing, in which we produce the ren-dered appearance of a scene from itsappearance in images. When usedeffectively, IBL can produce realisticrendered appearances of objectsand can be an effective tool for inte-grating computer graphics objectsinto real scenes.Illuminating synthetic objects with reallight IBL is now supported by several commercial ren- derers, including LightWave 3D, Entropy, and Blender.For this tutorial, we’ll use the freely downloadableRadiance lighting simulation package written by GregWard at Lawrence Berkeley Laboratories. Radiance isa Unix package, which means that to use it you’ll needto use a computer running Linux or an SGI or Sunworkstation. In this tutorial, we’ll show how to performIBL to illuminate synthetic objects in Radiance in justseven steps.