A method for depth mapping includes providing depth mapping resources, including a radiation source, which projects optical radiation into a volume of interest containing an object, and a sensor, which senses the optical radiation reflected from the object. The volume of interest has a depth that varies with angle relative to the radiation source and the sensor. A depth map of the object is generated using the resources while applying at least one of the resources non-uniformly over the volume of interest, responsively to the varying depth as a function of the angle.