Nikon D750 Product Manual - Page 384

f2: Assign Fn Button G button ➜ A Custom Settings menu Choose the role played by the Fn button, either by itself (Press) or when used in combination with the command dials (Press + command dials). ❚❚ Press Selecting Press displays the following options: Option q Preview r FV lock B AE/AF lock C AE lock only E AE lock (Hold) F AF lock only A AF-ON s Flash off Description During viewfinder photography, you can preview depth of field while the Fn button is pressed (0 92). During live view photography, you can press the button once to open the lens to maximum aperture, making it easier to check focus; pressing the button again restores aperture to its original value (0 56). Press the Fn button to lock flash value (built-in flash and compatible optional flash units only, 0 190, 435). Press again to cancel FV lock. Focus and exposure lock while the Fn button is pressed. Exposure locks while the Fn button is pressed. Exposure locks when the Fn button is pressed, and remains locked until the button is pressed a second time or the standby timer expires. Focus locks while the Fn button is pressed. Pressing the Fn button initiates autofocus. The shutter-release button can not be used to focus. The flash will not fire in photos taken while the Fn button is pressed. 356