1. A method for the three-dimensional digitization of objects ( 2 ) with a 3D sensor ( 10 ), which comprises a projector and one or more cameras, in which a pattern is projected onto the object ( 2 ) by the projector and the pattern is detected with the one or more cameras, wherein with the 3D sensor ( 10 ) at least three reference marks ( 14 ) and/or a reference raster are projected onto the object ( 2 ), and the reference marks ( 14 ) or raster are detected with-two or more external, calibrated digital cameras ( 12 ).