Separate reception/transmission apertures enhance pointing: reception is more efficient than transmission (kept smaller for MEMS steering). Apparatus aspects of the invention include lidar transmitters emitting laser beams, and scan mirrors (or assemblies) angularly adjustable to deflect the beams in orthogonal directions. In one aspect, afocal optics magnify deflection; a transmitter aperture transmits the beam; a lidar receiver doesn't share the transmitter aperture. In another aspect, auxiliary optics calibrate the deflection.