An apparatus and method for non-destructive inspection of materials housed in containers involves orienting an X-ray beam emitter and detector to direct and detect an X-ray beam at an angle substantially parallel to a sloped surface of the container to be inspected. A first X-ray apparatus is located opposite a second X-ray apparatus, and both the first and second X-ray apparatus are adapted to provide two X-ray beams. This arrangement provides for imaging of the entire area of a sloped portion of the container without any shadow or hidden spots.