Increasing emphasis is being placed on the quantitative aspects of neutron radiography as an aid in characterizing reactor fuel specimens nondestructively. In general, precise dimensioning from radiographs requires some aid to remove subjectivity from film interpretation; photographic image enhancement was the aid used in this study. The fundamental limitation in determining physical dimensions from radiographs is shown to be related to the ability of the neutrons in the inspection beam to penetrate the samples. Neutron penetration is dependent on parameters other than physical size, so it is reasonable to expect differences between physical dimensions and dimensions derived from radiographs.