A three-dimensional object of a desired shape is made by irradiating an optical beam on a metal powder layer to form a sintered layer and by laminating such sintered layer one above another. The compositions comprise a polyepoxide and a material having the structure 1wherein R1 is an organic radical having 6 to 25 carbon atoms; R2 is an organic radical having 1 to 20 carbon atoms; R3 and R4 are independently alkyl or phenyl groups having 1 to 8 carbon atoms; Z is oxygen or nitrogen, and when Z is oxygen R5 is absent and when Z is nitrogen R5 is hydrogen or is 2and n is 1 to 4. The imaging system may also include a plurality of stereo camera supersets, wherein a first one or more stereo camera supersets are positioned at a different height relative to a first stereo camera superset. As an example, in the first mode of operation, the antenna assembly can operate as a one-half wavelength antenna.