Sensitometric evaluation of a new F-speed dental radiographic film

Objective: To compare a new experimental Kodak (Eastman Kodak, Rochester, N Y, USA) F-speed dental X-ray film with Ektaspeed Plus and Ultra-speed. Methods: The three types of film were exposed and processed under standardi zed conditions. Values of base plus fog, speed, and film contrast were deri ved. Resolution was compared by a line-pair plate. Results: Under these experimental conditions, the speed of the new film was just into the F-speed range, and a little over twice as fast as Ultra-spee d. The Ektaspeed Plus emulsion was somewhat slower than previously recorded when it was first introduced, but around the centre of the E-speed range. Ektaspeed Plus and the new F-speed him had almost identical film contrasts, the F-speed film having slightly greater contrast in the higher density ra nge. Ultraspeed contrast was marginally greater in the lower density range, but was overtaken by both of the other emulsions at higher densities. All three emulsions had low values of base plus fog. Both E- and F-speed films resolved 10 line-pairs per millimetre well, though both emulsions were infe rior to Ultra-speed. Conclusions: The new F-speed film, since marketed as Insight, provides a fu rther saving in radiation exposure, with no evident deterioration in him co ntrast or resolution.