A 3D modelling system for three-dimensionally modelling a scene by multi-view photogrammetry, which system comprises cameras (C1 to C8, C1' to C8', C1" to C8'' and C1''' to C8''') that are designed to be grouped together in pairs (C1-C4, C2-C3, C5-C6, C7-C8) of cameras that are placed around the scene to produce images of said scene with different viewpoints, the cameras in each pair of cameras having a certain intra-pair spacing (e) between them, and a digital processing device that, from the images produced by the cameras, is configured to produce modelling data by applying stereoscopy processing by comparison between the images produced by respective ones of the two cameras of each pair (C1-C4, C2-C3, C5-C6, C7-C8) of cameras, in which system: said pairs (C1-C4, C2-C3, C5-C6, C7-C8) of cameras are distributed around the scene in such a manner as to have inter-pair spacings (Ela, E1b, E1c, E2a) between two adjacent pairs of cameras that are larger than said certain intra-pair spacing (e); and said digital processing device is further configured in such a manner as to apply stereoscopy processing by comparison between the images produced by a camera of a first pair (C5-C6) of said pairs of cameras and the images produced by a camera of a second pair (C1-C4) of said pairs of cameras, the second pair (C1-C4) of cameras being adjacent to the first pair (C5-C6) of cameras and spaced apart from said first pair of cameras by an inter-pair spacing (E1c) that is greater than the intra-pair spacing (e), in order to produce additional modelling data, said modelling system being characterized in that: the cameras of said first pair (C5-C6) of cameras are arranged side-by-side substantially in a same horizontal plane (HP2'); and the cameras of said second pair (C1-C4) of cameras are arranged one above the other substantially in a same vertical plane. said pairs (C1-C4, C2-C3, C5-C6, C7-C8) of cameras are distributed around the scene in such a manner as to have inter-pair spacings (Ela, E1b, E1c, E2a) between two adjacent pairs of cameras that are larger than said certain intra-pair spacing (e); and said digital processing device is further configured in such a manner as to apply stereoscopy processing by comparison between the images produced by a camera of a first pair (C5-C6) of said pairs of cameras and the images produced by a camera of a second pair (C1-C4) of said pairs of cameras, the second pair (C1-C4) of cameras being adjacent to the first pair (C5-C6) of cameras and spaced apart from said first pair of cameras by an inter-pair spacing (E1c) that is greater than the intra-pair spacing (e), in order to produce additional modelling data, said modelling system being characterized in that: the cameras of said first pair (C5-C6) of cameras are arranged side-by-side substantially in a same horizontal plane (HP2'); and the cameras of said second pair (C1-C4) of cameras are arranged one above the other substantially in a same vertical plane. the cameras of said first pair (C5-C6) of cameras are arranged side-by-side substantially in a same horizontal plane (HP2'); and the cameras of said second pair (C1-C4) of cameras are arranged one above the other substantially in a same vertical plane.