Recovering the light sources from images in which the objects can move is difficult both because the specularities travel along the surfaces and because diffuse reflections do not remain constant. In this paper, we show that this can nevertheless be done without making the very restrictive assumptions that are usually made provided that 3D models of some scene objects are available or can be computed. Our approach involves following local gray-level maxima and deciding whether or not they represent specularities. The true specularities are then used to count how many light sources are in the scene, compute their precise location and estimate the material properties.