A subsystem is disclosed providing a steerable-beam light source. An array of micromechanical reflectors may be disposed to selectively direct portions of light from a light source to selected targets in a scene, such as for providing composed illumination for still or video photography. The array of reflectors may be continuously steerable, thereby achieving more than the mere inefficient patterning of illumination light available from prior art projection approaches, but instead efficiently redirecting light to the desired regions of the scene. The subsystem may be sufficiently compact so as to permit integration with a compact camera into a cellular telephone, a tablet computer, a laptop computer, a digital still-image camera, a digital video-image camera, and so on. The array may be operated in conjunction with a camera controller to selectively illuminate one or more targets of focus or zoom, omit illumination of undesirable image regions, etc.