An X-ray apparatus is provided for inspecting a cargo container. The apparatus includes a moveable platform with an X-ray source and X-ray detector disposed on the platform on opposing sides of a scanning zone where the scanning zone may be moved along a length of the cargo container to scan a volume of the cargo container, said X-ray source being disposed in a spaced-apart relationship with respect to the scanning zone. The X-ray apparatus also includes a precollimator disposed on the X-ray platform between the X-ray source and scanning zone, said precollimator being located proximate the scanning zone and an intermediate collimator disposed midway between the X-ray source and the precollimator, said intermediate collimator having a spaced-apart relationship with respect to the precollimator and to the X-ray source.