Nikon D3400 Reference Manual page 290

The SB-5000, SB-910, SB-900, SB-800, SB-700, SB-600, SB-500, and
SB-400 provide red-eye reduction, while the SB-5000, SB-910, SB-900,
SB-800, SB-700, SB-600, and SU-800 provide AF-assist illumination with
the following restrictions:
• SB-5000: In the case of
24–135 mm AF lenses, AF-assist
illumination is available with the
focus points shown at right.
• SB-910 and SB-900: In the case of
17–135 mm AF lenses, AF-assist
illumination is available with the
focus points shown at right.
• SB-800, SB-600, and SU-800: In the
case of 24–105 mm AF lenses,
AF-assist illumination is available
with the focus points shown at
right.
• SB-700: In the case of 24–135 mm
AF lenses, AF-assist illumination
is available with the focus points
shown at right.
Depending on the lens used and scene recorded, the in-focus indicator
(I) may be displayed when the subject is not in focus, or the camera
may be unable to focus and the shutter release will be disabled.
266 Technical Notes
24–37 mm
17–135 mm
24 mm
24–135 mm
38–135 mm
25–105 mm