Custom button map
How do you assign the custom controls on a Nikon Z8 — including the vertical shooting buttons other bodies do not have?
Work at the f2 desk
All stills assignments are made at Custom Setting f2: highlight a control, press the center button, choose a role. The bench includes Fn1, Fn2, the vertical trio, Protect/Fn3, AF-ON, the sub-selector center, the video record button, the BKT, WB and release mode buttons, the command dials, lens controls, and the controls of the optional MB-N12 power battery pack. Video assignments live separately at g2 Custom controls — a map built for stills does not follow you into video mode.
The vertical trio
The Fn button for vertical shooting, the AF-ON button for vertical shooting, and the vertical multi selector center exist only for portrait orientation — and all three are assignable. Give the vertical Fn the same role as Fn1 (this lesson: Cycle AF-area mode) so the tool follows your hand when the camera rotates.
Distances on buttons
Save focus position memorizes a focus distance (to all recall controls, or individually); Recall focus position snaps the lens back to it. Preset focus point jumps to a placed point, with Custom Setting a5 storing points per orientation. The Focus limiter role toggles Custom Setting a16 and, held, opens its Limit range — fencing out distances the lens would otherwise hunt through.
The lens is a control surface
Lens Fn and Lens Fn2 buttons, the control ring, the Lens Fn ring in each direction (two separate roles), and the Lens memory set button are all assignable. Power zoom lenses add Save and load power zoom position. The finished map lives in your Custom Settings bank; Setup Menu → Save/load menu settings can write the whole configuration to a card.
Assign Fn1 and the vertical Fn to Cycle AF-area mode, save a focus position across the room, focus away, then recall it. The lens returning by itself is the map working.