A method and a system for creating a collective point-cloud data from a plurality of local point-cloud data including the steps of: providing scanner data containing a plurality of local point-cloud data and relatively low-precision positioning data of the scanner providing the local point-cloud data, creating a relatively medium-precision collective point-cloud data from the plurality of local point-cloud data using external (medium-precision) positioning data associated with each of said plurality of local point-cloud data, and then creating a relatively high-precision collective point-cloud data from said medium-precision collective point-cloud data.