AF-Assist Illuminator UsageThe built-in AF assist illuminator enables the camera to focus even when the subject is poorly lit. To use the illuminator, the camera must be in single-servo AF with an AF-Nikkor lens attached, and the center focus area must be selected or closest subject priority in effect. If these conditions are met and the subject is poorly lit, the illuminator will light automatically to assist the autofocus operation when the shutter-release button is pressed halfway. For the AF-assist illuminator to function correctly, the lens must have a focal length of between 24 and 200 mm and the subject must be in range of the illuminator.With most lenses, the illuminator has a range of about 0.5 to 3 m (1´8" to 9´10"). With the following lenses, the illuminator cannot be used at ranges of under 1 m (3´3"):AF Micro ED 200 mm f/4AF-S ED 17–35 mm f/2.8AF ED 18–35 mm f/3.5–4.5AF 20–35 mm f/2.8AF 24–85 mm f/2.8–4.0AF 24–120 mm f/3.5–5.6AF-S ED 28–70 mm f/2.8AF Micro ED 70–180 mm f/4.5–5.6The built-in illuminator will not light when used with the AF and AF-S ED 80– 200 mm f/2.8 and AF VR ED 80–400 mm f/4.5–5.0.If an optional SB-series 80DX, 50DX, 28DX, 28, 27, 26, 25, or 24 Speedlight is used, the camera's built-in AF-assist illuminator will turn off and the Speedlight illuminator will be used instead. With other Speedlights, the camera's built-in AF assist illuminator will be used. Print Share By Email Share By Social Ask A Question FaceBook Twitter