Dynamic AF
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Nikon advanced feature mode, intended to be used with Continuous (C) Servo AF and Continuous film advance for tracking moving subjects in advanced camera models. As soon as you half depress the shutter release button the AF locks onto the subject within the primary (pre-selected) focusing area. Even if the subject moves out of the selected focusing area, the AF will continue to lock on it as the nearest focusing area takes over since the camera has been not just focusing but also computing the subject's speed and motion direction. Even if the subject gets obscured by some other object, the F5 will not loose track as it is anticipating the subject's location. This feature has been rated to follow up to 20mm per second across the film plane, the equivalent of this with a 300mm lens is a subject moving at 300 kmph (186.5 mph) up to a distance of approximately 20 meters (61 feet). As Gunther Richter wrote in the Magic Lantern Guide for the F5: "Now, try that with any other camera!"
