A cinefluorography produces a movie (cine) film from an image intensifier during x-rays examinations (often called videofluorography, cineradiography or cine). Cinefluorography is always monitored on the TV screen normally used for fluoroscopy. The image from the output screen of the image intensifier is split with a semi-transparent mirror into two output ports; one leading to the movie camera and the other to the fluoroscopy camera. Most of the light is directed to the cine camera. The image on the monitor does not suffer in quality due to the fact that the tube current for cinefluorography is about 100 times higher than for common fluoroscopy.
The x-ray generator pulses are synchronized with the movements of the cine camera, so that no x-rays are emitted when the film is moved forward to the next frame. The needed very accurate synchronization of the x-ray generator can be achieved by use of high voltage switching in the secondary circuit of the constant potential x-ray generator, by starting and stopping the inverter in a medium frequency generator or by using a grid controlled x-ray tube.

An intensifying screen is used to intensify the x-ray effect during radiation exposure of the x-ray film. Approximately 5% of the x-ray photons will be absorbed by the film only. Intensifying screens consist of a sheet of inorganic salts that emits fluorescent light when stroked by x-rays. The fluorescent input and output screens of the image intensifier are very similar to intensifying screens.
Calcium tungstate and rare earths are two common salts (also called phosphors) used for intensifying screens. For example, a calcium tungstate (CaWo4) screen can absorb around 40% of the x-ray photons and convert the radiation into light photons. A basic feature of this screen types is related to the position of the k-edge on the energy axis. Tungsten (W) is a heavy element has a k-edge at 69.5 keV, while that for rare earth elements is in around 50 keV.
The fraction of x-rays absorbed by a screen is depending on the speed. Factors affecting the speed of a screen: Mammography cassettes contain usually one intensifying screen, but most others use two screens per film cassette. The intensifying screen as part of a film screen system has been an important component in radiology to reduce the radiation dose of the patient. Today, the conventional film cassette is being replaced by an imaging plate used in digital systems.

See also Actinides, Cinefluorography and Added Filtration.