Nikon F 4 - Page 29

The scale on the dial has numbered settings for speeds from ISO 6 to 6400. Two
dots between each pair of ISO numbers stand for intermediate settings. Every posi-
tion is locked in 1/3 EV steps. The table above shows the speeds for all intermediate
settings.
Manual Film Speed Setting
While pressing the lock release, set the film speed dial to the film's
ISO number.
If DX-coded film is loaded, but the film
speed is set manually, the camera gives
priority to the manually set ISO number.