Because photographic plates are sensitive to X-rays, they provide a means of recording the image, but they also require much X-ray exposure (to the patient). The addition of a fluorescent intensifying screen (or screens) in close contact with the film allows a lower dose to the patient, because the screen(s) improve the efficiency of x-ray detection, making more activation of the film from the same amount of x-rays, or the same activation of the film from a smaller amount of x-rays.