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This paper describes a cineradiography system in use at the Los Alamos National Laboratory, as related to the advantages and disadvantages over conventional flash x-ray systems. Traditionally, x-ray imaging techniques in dynamic testing have relied on creating extremely short pulses of radiation to freeze the motion of the object, and then recording the image on film by means of fluorescent intensifying screens to obtain sufficient image density on the film. This results in images often limited only by the resolution of the film-screen combination, which are usually of reasonable quality. In a cineradiography system, two basic differences are evident. First, the radiation source emits continuously for the duration of the experiment. Second, the film is replaced by a gated, intensified television camera focused on the fluorescent screeen. The image is frozen by the short gate time of the camera, rather than by the short pulse of radiation. One advantage of the television system is that the camera can be considerably distant from the screen, and if the screen is sacrificial, mechanical protection requirements are alleviated or eliminated. Another advantage is that several cameras can be focused on the same screen, allowing multiple images to be made with the same geometry. A third advantage is that the spot size of the radiation source is small, thus reducing geometrical limitations on resolution. The disadvantages of this system relate to the use of the television camera to record the image(s). Neither the resolution nor the contrast of the intensified television camera is as good as film, and this limits the quality of the image that can be produced. However, flash radiographs are often of relatively poor quality because of the limited amount of radiation available from the source and the graininess of the high-speed film required, so this is often not an important difference.
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