Traditionally, multiple format recording emulsions for medical video imaging have utilized a film (transparent) base. The major reason for this is probably because the film and camera manufacturers felt the diagnostician is accustomed to viewing x-ray images on a film base and would prefer to view video images that way also. Because of the need to keep radiation exposure to patients at a minimum and the fact that photographic emulsions are generally very inefficient in utilizing x-ray radiation, a film base was the logical requirement for direct x-ray imaging as it enabled the image to be recorded by two emulsions rather than one. The transparent base thus allows viewing a photograph which is the result of the additive effect of the two emulsions. The use of transparent base imposed specific requirements that necessitated the development of a whole complex of equipment designed for the particular use of film such as the processing machines, their chemical solutions, and the famous viewbox and alternators that characterize the radiology departments of today.