On the rear panel of Nikon’s high-end DSLR bodies, including the D300, D700 and D3 series cameras, you’ll find a little button marked “AF-On.” It seems kind of redundant to use this button for focusing when a half-press of the shutter release does the same thing. Actually, I’ve found that setting the AF-On button to be the only way to activate AF is the best way to operate my Nikon’s AF system, but it requires a few set up steps and a little practice.
Why should you use the AF-On Only Technique with your Nikon DSLR?
The idea behind setting the AF-On button to be the only way to activate your Nikon’s autofocus system is simple. Doing so allows you to set the camera to continuous-servo AF (AF-C) mode permanently, while still being able to get the benefit of focus-lock like you do in single-servo (AF-S) mode. This means that at any time, you can switch between a focus/recompose/shoot style of photography (portraits and landscapes) and continuous subject tracking (sports & wildlife) without having to change camera switches or menu settings.
Also, with this technique, you decouple VR activation (half-press of shutter release) from AF activation. That means you can be tracking a subject with AF and only engage VR when you want to. This technique can save battery life in your camera!
How to set up y0ur Nikon DSLR to use AF-On as the focusing mechanism
The AF-On button is located on the back of most professional-level Nikon DSLRs
- Verify that your camera has an AF-On button. If not, you’ll need to set up the AE/AF-lock button in the custom menus to use it as the AF-On button. In the Nikon D90, this is custom setting f4.
- Set the camera’s AF servo mode to Continuous (AF-C). This is done through the switch next to your lens mount, or via a custom menu setting. D90 users: hold down the AF button on the top of your camera, and turn the Main Command Dial until AF-C is displayed in the top LCD panel.
- In the camera menus, go to submenu “a” (Autofocus)
- Set custom setting a1 (Continuous Release Mode) to Release Priority (in the D90, this is already set for you when you choose continuous servo AF mode)
- Find the custom setting for AF Activation (a5 on the D3s) and set it to AF-On Only. This step is not necessary for the D90 and other cameras, as it is already set up by custom setting f4.
Now you’re all set up and ready to go.
How to use the AF-On technique in the field
To emulate single-servo mode (focus/recompose/shoot)
- Place the active AF point on your subject
- Press the AF-On button to acquire focus
- Release the AF-On button to lock focus
- Recompose and shoot
To focus continuously on a moving subject
- Place the active AF point on the subject
- Press the AF-On button
- Keep the AF-On button pressed to track focus while simultaneously pressing the shutter release
- Remember to initiate the VR system (if your lens supports it) by half-pressing the shutter button prior to releasing the shutter. Remember, VR takes about a half-second to stabilize, so you’ll want to anticipate your subject.
Now that you understand how to use the technique, you’ll want to spend some time practicing. It usually takes about a day of shooting in the field to get used to the new technique. Once you know how to use it, the AF-On only method of focusing will help you get more “keeper” shots.
I love this technique and have been using since you and Rick first talked about it a couple of years ago. Now it just feels wrong to use a camera without it.
Jason,
I was trying to figure out how to do that after I heard about it on the Image Doctors Podcast. I got caught last week in the situation you described. I was getting a few shots at a stationary Blue Heron, but then saw geese coming in for a landing. Even though I thought I was focusing right, it didn’t come out. I think this may help. Going to try this technique tommorow.
On my D200, I don’t have a “release priority” setting for step 4. Can I still use this AF-on mode to track moving subjects?
It’s custom setting a1, and you set it to FPS Rate.
I have been using the AF-On for some time but not on continuous. Nice to know about the tracking feature. My D300 is so fast on C that I have to be very careful so if I set it to S on the top dial but leave the the C setting on the front, will I have everything except the tracking? Then change to C on top dial if desiring to track….
Pingback: For All Things Nikon » Blog Archive » Nikon DSLR AF-On Button Technique
Hi Jason,
Great Post. Thanks for the info. We had talked about this in Connecticut.
The video image and link at the top of this post is not displaying at all for those of us using Firefox. It is just showing up as a white box with the alt text. It is only displaying properly in Safari for us Mac folks. Are you using any thing there that would be blocked of not recognized by Firefox?
Thanks for the heads-up, John. I’ve fixed the image and link and it should work now.
-Jason
This might be really dumb, but for static and relatively static subjects does it matter if you use single point or dynamic area AF while using this technique?
I would use single-point AF at all times unless your subject is moving.
Hi Jason,
I’ve watched your AF-ON youtube video and this sounds like a great technique. I’d like to try it on my venerable D1X, but my menu options are a bit different than the new cameras. I think I’ve got it set up properly, but could you possibly give me some hints as to how to set up this older model?
Thanks,
Mark E.
does this work on D7000?
1. is the green dot light suppose to stay on after i focus?
2. i do not hear the beep sound when i focus, is it normal?
3. the af selection button will get hang after sometime and i only see a single af point with AF-S on the top LCD screen. but everything back to normal once i unlock n lock the lens again.
I find this technique somewhat inconvenient with fast primes (1.4-2.0) because you can’t just focus-and-recompose from central point with off-centered subjects due to shallow DOF. I prefer to leave my thumb on focus point selector and change focus point as fast as possible. Hence no way for me to activate AF rather than half-pressing shutter release button.
Jason,
Great post! I first tried this when I heard you mention it on Images Doctors a couple of years ago. It took a while before I felt comfortable giving up holding the shutter release button, but have since found it so much easier to compose a shot.
I had been reverting to AF Activation set to Shutter/AF-ON when shooting sports, but didn’t realize the disadvantage of the VR current drain. From now on I will leave setting to AF-ON only and track action while depressing that button.
Thank you for the excellent insight and clear explanation.
Is there any drawbacks to using AF-ON Button for both Single & Continuous focus?
Does VR work in both scenarios providing you give it ample time (one second?)
What about exposure?
Thanks,
Bob
Bob-
VR is always activated with a half-press of the shutter. It works the same. Exposure is not affected. The only limitation of the technique is when you’re using a speedlight with AF-Assist lamp. The AF-assist lamp only works in AF-S mode.
-Jason
Know this comment/question is belated, but…
Love the technique…except when I want to use AE lock and the AF-On button on my MB-D10. Half-press of shutter button to lock AE (CSM c1 on my D300) OK but sub-optimal solution, as the MB-D10 shutter release button is hyper-sensitive. Would really like to keep using the AE lock button.
Has anyone mastered this or have any handy tips or tricks?
I am lost how to use this method with my 70-200 VR lens,could you please help
Winston-
The lens makes no difference; what matters are the in-camera settings for AF. If your camera does not have a dedicated rear “AF-ON” button, then you’ll need to customize your AE-Lock button to serve as an AF-ON button. With the 70-200VR lens, just make sure it’s set to use Autofocus (A/M) switch in the “A” position (or for the VRII model, “A/M” position).
Thanks a million, I have just tried this setup it is great.
Just one more question, when I use fill in flash with this system does the auto focus on the SB800 still work?
Bye the way my camera is a D700
Hi,
I know this is an old post but had to stop by and say THANK YOU. I’ve been exploring back button focus for a bit now but these are the clearest instructions and explanations I’ve found yet. Thanks again!
Request: please, would do a similar video just on the L lever on the back of higher-end nikons. I think it locks exposure, but how does it affect focus, probably not at all?
The AE-AF lock button can be customized to lock exposure or the focus point. It does not affect focus by itself.
The AF-Assist lamp will not operate with this technique. For that, you need to have the camera in single-servo (AF-S) mode.
THANK YOU!!!!
I have been fighting my autofocus for months until I found this post.
I used to be able to do this with my film camera and was frustrated I couldn’t figure it out on the D90. WOW!!
Pingback: Midnight in the Garden | Luminescence of Nature™
I have a D7000 When I focus from back button (still object) release the button and recompose the shutter will not fire. I have all settings per your video. Call Nikon they say the focus has to be in AFS other wise will have to be refocus after you recompose. Please help. bob
Robert-
The only way this technique works is if:
a) Camera is in continuous-servo AF (AFC)
b) shutter release is not set to activate AF (AF-ON or AE-lock button only)
If these two conditions are not met, the technique won’t work. In single-servo AF, your camera won’t fire at all unless it thinks focus is locked. If you move the camera AF sensor to an out of focus object (as what happens when you recompose), it “sees” an OOF object and won’t fire.
If you have the shutter release button set to activate AF, then when you recompose, the camera will re-focus when you try to take the shot because you’ll be activating AF when you release the shutter.
With your D7000, what you need to do is this:
Set Custom Setting f5 to AF-ON. This sets the AE-L/AF-L button to function as the AF-ON button, and disables AF activation from the shutter release.
Set the camera to AF, press the AF mode button, and rotate the Main Command Dial until AF-C is displayed in the control panel. By default, this will put the camera into “release priority” mode as described in the article.
Pingback: Explanation of what back button focusing is and how to do it on a DSLR. | Everyday Elements
Thank you SO MUCH! This was the best explanation of BBF for Nikon I have seen! I have been trying to do this for months! I have a D7000 and had to change the AF-C priority mode to Release, though. It did NOT do that automatically, and the shutter wouldn’t release (did not do it by default). Can’t wait to really try this out tomorrow!
Thanks for the explanation, but do you have any idea how to do this on a Nikon D60?
Thank you SO MUCH for this post! Such a clear, concise explanation — you’re a natural teacher!
Carmen-
I believe you’d need to customize the AE-L button to serve as the AF-ON button, and make sure your camera is set to continuous servo AF mode.
Since I don’t have a D60, I’m not familiar with the specifics, but the manual should have that information.
Thanks, Christa!
I was pointed to this link from the e-book “Tack Sharp” by James Brandon (he is of the Canon breed). As alot of my shots where not in focus, I thought I would give this a try. I have the D300s and have now set it up as instructed. It looks easy to use and will be out practising very soon. I like taking shots of birds on the garden table, so I am sure this new method will help with both static and moving shots. Thanks for the clear and precise instuctions.
Hi Jason,
Great article but based on some posts here. I am still not clear. Please advice:
1. Your response on 05/16/2011
The AF-Assist lamp will not operate with this technique. For that, you need to have the camera in single-servo (AF-S) mode.
Does that mean when I use flash, I have to switch the focus mode in front of the camera back to AF-S? And reset menu “a5″ back to Shutter/AF-ON.
2. Marat’s post on 01/14/2011
I find this technique somewhat inconvenient with fast primes (1.4-2.0) because you can’t just focus-and-recompose from central point with off-centered subjects due to shallow DOF. I prefer to leave my thumb on focus point selector and change focus point as fast as possible. Hence no way for me to activate AF rather than half-pressing shutter release button.
Please confirm if this true.
Kevin-
To answer your questions:
1) The AF-assist lamp only works in single-servo AF mode, but you can still use the AF-ON button to focus. These functions are independent of each other.
2) I think this post has more to do with Marat’s preference of using the D-pad to move the active focus point while composing. I don’t believe this is an issue with the technique, just a personal preference. You can still recompose and shoot just like single-servo mode. I think Marat is trying to keep focus on a specific area with a very shallow DOF. One work-around would be to use the 51-point subject tracking AF mode, which will stay on your original subject while you recompose.
I’m new with this technique and struggling when I shoot with the camera off of my eye. Examples, holding the camera at your feet to track sea turtle hatchlings… or… above your head at a concert.
Can someone please sell me on the thumb technique for these off the eye situations? Thanks,
Pete
Pete-
Those are the situations (especially with one-hand shooting) where I think it’s physically easier to use the Shutter button for AF. For me, at least, it’s just easier to hold the camera. Maybe I need to start working out more.
Thanks Jason for the quick reply. I very much appreciate the info as I’ve been wanting to try this out for a long time but never found the right instruction until now.
Happy Holidays
Pete
Thanks Jason for your quick reply.
Would you please share your settings on a D2X?
Any other custom settings from a – f which would be beneficial to this AF-ON function?
Currently my settings:
ạ5 = AF-ON only
a8 = AF-ON + Focus area
c2 = AE Lock Hold
c3 = 16s
f4 = Same as AE-L/AF-L
Excellent tips AF-ON
How do I setup AF-ON on Nikon D200? Please help.
Thanks
Should be very similar to the setup for the D300.
Make sure the camera is in AF-C mode (front lever)
Make sure that the shutter is set to release priority
Make sure that you disable the shutter release button from activating AF.
Jason,
Thanks for quick reply,
Here is what I did on D200 as below
1. Set custom function a6 AF Activation to AF-ON Only
2. a1 AF-C Mode Priority to FPS Rate
3. a5 Lock-on -> Set to Short or off
4. AF-Area Switch (rear) set to Single Area ( Lowest setting) . ? I’m Not sure this option
5. Front AF- Mode Switch to C /AF-C mode.
Please verify and advise.
Thank,
John
Can you comment on what the impact of this BBF AF-ON has when using the Nikon mll3 remote? Will the remote let the camera AF without having to adjust settings? I have a D7000. Thanks.
Tony-
I don’t have a D7000 to test. I’d suggest trying it for yourself to see what happens.
-Jason
John-
Set a1 to Release Priority, not FPS Rate
a5 can be whatever you’d like
AF area can be whatever you’d like, although single-area is fastest
Everything else is fine.
-Jason
Yip, this technique really works well – I have been using it on my D700 and Fuji S5Pro for more than a year now – I would hate to work differently now !
Pingback: Do you use AF button for focusing?
Terrific post, thank you. In case it’s of interest to anyone, I posted last year on my blog a slightly different take on the same AF-ON question:
http://blog.arcanedomain.com/2010/10/dslr-hint-whats-that-af-on-button-for-anyway/