A three-dimension distance time-of-flight system is disclosed in which distance values are acquired by a plurality of sensors independently from each other. For use with this and similar systems, Z-distance accuracy and resolution are enhanced using various techniques including over-sampling acquired sensor data and forming running averages, or forming moving averages. Acquired data may be rejected if it fails to meet criteria associated with distance, luminosity, velocity, or estimated shape information reported by neighboring sensors. A sub-target having at least one pre-calibrated reflectance zone is used to improve system measurement accuracy. Elliptical error is corrected for using a disclosed method, and reversible mapping of Z-values into RGB is provided.