How to Set Back Button Focus – Nikon Z9 and Z8

Because Your Thumb Deserves the Spotlight

Back Button Focus on the Nikon Z9 and Z8 – Because Your Thumb Deserves the Spotlight

Birders of Texas, lend me your ears—and more importantly, your thumbs.

Today’s tutorial is all about giving your autofocus game an upgrade, specifically with the mighty Nikon Z9 and Z8. If you’re still focusing by half-pressing the shutter button, you’re basically living in the birding Stone Age (bless your heart). It’s time to join the modern bird photographer’s club with Back Button Focus (BBF)—a technique so elegant, you’ll wonder why Nikon doesn’t ship cameras with it turned on by default.

What Is Back Button Focus?

Back Button Focus separates autofocus activation from the shutter button. That means your shutter finger takes the photo and your thumb does the focusing. It’s like dividing household chores—only nobody argues.

Why is this magical for birders?

• Track the bird without refocusing every time you half-press.
• Focus and recompose without the camera panicking and locking onto a branch instead.
• Fast action shots without the lag of refocus. Think diving terns or zipping warblers.

In short, your thumb becomes your bird-chasing co-pilot.

How to Set Up Back Button Focus on the Nikon Z9 or Z8

Step 1: Disable Focus from the Shutter Button

Let’s relieve the shutter button of its focusing duties.

1. Hit the Menu button.
2. Go to the Custom Settings Menu (the pencil icon).
3. Navigate to a4 – AF activation.
4. Change this from Shutter/AF-ON to AF-ON only.
5. Hit OK.

Boom. Your shutter now only takes pictures—no sneaky refocusing.

Step 2: Assign Autofocus to the Back Button (AF-ON)

Nikon, in its infinite birding wisdom, already included an AF-ON button on the back of your Z9/Z8. If it’s not active or you want to remap something else:

1. In the Custom Settings Menu, go to f2 – Custom control assignment.
2. Select AF-ON (or choose another button if you’re a rebel).
3. Assign it to AF-ON.
4. Press OK.

Congratulations, your thumb now has a real job.

Step 3: Optional – Add a Bird Detection Button for Instant Avian Warfare

Want to go full birder-Jedi? Assign a second button to instantly launch bird subject detection.

1. Still in f2 Custom control assignment, choose Fn1 or Fn2 (or even the movie record button if you’re feeling bold).
2. Set it to Recall shooting functions (hold).
3. In the submenu:
   • Enable AF area mode and set it to Wide-Area AF (C1) or your favorite.
   • Turn on AF subject detection, select Bird.
4. Hit OK.

Now, holding that button activates your specialized bird-hunting AF setup. The moment you press it, the camera goes into “Bird Mode” like a raptor locked on target.

Real Talk: It Takes Getting Used To

Let’s be honest. You’ll forget to use your thumb at least twice. Maybe twelve times. You’ll press the shutter halfway and whisper to yourself, “Why won’t this dang thing focus?” It’s part of the journey.

Give it a day or two. Soon, it’ll become second nature—especially when that rare Scissor-tailed Flycatcher swoops in and you nail the shot like a pro.

Final Thoughts – Thumb and Glory

Once you go BBF, you don’t go back. You’ll wonder how you ever trusted that twitchy little shutter button with your focus. Your thumb, steady and dedicated, will lead you to better bird shots, fewer missed moments, and far fewer images of branches where a bird used to be.

Go forth, Z9 and Z8 users. Thumb responsibly.