Nikon 13187 User Guide (en)

Choose the role played by the depth-of-field preview button during movie live view. 
The options available are the same as for Assign Fn button (
0 247), except that the 
default setting is Index marking.
Choose the role played by the 
AE-L/AF-L button during movie live view. The options 
available are the same as for Assign Fn button (
0 247), except that the default 
setting is AE/AF lock.
Choose the role played by pressing the shutter-release button when 
1 is selected 
with the live view selector.
g2: Assign Preview Button
G button
➜ A Custom Settings menu
g3: Assign AE-L/AF-L Button
G button
➜ A Custom Settings menu
g4: Assign Shutter Button
G button
➜ A Custom Settings menu
Take photos
Press the shutter-release button all the way down to end movie recording 
and take a photograph with an aspect ratio of 16 : 9 (for information on 
image size, see page 63).
Record movies
Press the shutter-release button halfway to start movie live view. You can 
then press the shutter-release button halfway to focus (autofocus mode 
only) and press it all the way down to start or end recording. To end 
movie live view, press the 
a button. The shutter-release button on an 
optional remote cord (
0 298) can be used to start movie live view and to 
start and end movie recording; the optional ML-L3 remote control, 
however, can not be used to record movies. In remote control (
4) mode, 
pressing the shutter-release button halfway does not start movie live 
view, while pressing the shutter-release button on the remote control 
releases the shutter to record a photograph and does not start or end 
movie recording.
Record Movies
When this option is selected, interval timer (
0 164) is not available and the shutter-release 
button can not be used during movie live view to record photographs, measure preset white 
balance, or record image dust off reference data. Select Take photos to use these options.