by Lisa Tichané
If you are an active member of the Clickin Moms photography forum, you have probably heard of it several times. At the very end of Lynne Rigby‘s Shooting 101 photography workshop, The Best Darn Beginner Course Ever, when she asks her students what their major AHA moment was, Back Button Focusing is often on top of the list. It was definitely one of my very own major light-bulb moment when I discovered it.
So what is back button focusing?
It’s a very simple thing that might change the clarity of your images forever.
When you auto-focus with your DSLR default settings, here is how it basically works: you press your shutter half way to auto-focus, and when your focus is OK you press your shutter a second time to take the picture. There is an alternative to this focusing method: you can decide that another button (the famous BBF, or “back button focusing”) will handle your focus.
Depending on your camera, you can use the AF-ON button (this is the one I am using on my Canon 5D MarkII), or the AF-L button for Nikon users, or even the star (*) button.
Why would you do that?
Simply because it separates your focusing from your shutter. Instead of asking your index finger to deal with two different things one after the other, you give it one single task (pressing the shutter at the perfect moment) while your thumb will deal with focusing.
There is a debate about BBF. Some have tried it and swear that they don’t see any difference. If you mainly photograph landscape or still life, it’s very likely that BBF won’t change your life. On the other hand, if you are a portrait photographer, and if your model is potentially moving fast (those who have a toddler at home, I can feel your attention growing!!), BBF is probably going to be your best friend.
Let’s try to understand why. Here is an image of two cute boys playing knights. They’re happily running towards the lens.
If you place your focal point on the first boy, press your shutter half way to focus and then press the shutter, there is a fraction of seconds between those two steps. This very short moment can be long enough to let the first boy step out of your focus zone. Especially if you were using a wide aperture, thus having a very shallow depth of field. As a result, you will get an unsharp image.
Fortunately, I was using BBF when I took this image (I use it all.the.time). I was also using a dynamic autofocus mode (Ai-Servo, the equivalent is AF-C if you are a Nikon user). Thus, I kept my thumb on the back button all the time, allowing my camera to continuously autofocus and follow the boy’s movement. When my index hit the shutter, my thumb was still pressing the back button so both actions happened simultaneously. As a result, my focus was spot on.
So BBF will guarantee a more precise focusing with any image involving a fast movement, like Hayden flying in the air or Etan jumping.
This is why BBF is very often used by sports photographers, or wildlife photographers (in order to capture a flying bird for example).
Note: this article is not covering all the aspects leading to sharpness, but don’t forget that to get a crisp image with a fast moving subject you also need a high shutter speed in order to freeze motion, like 1/500s or 1/640s in the two examples above.
Another interest of BBF is that it locks your focus.
If you press your thumb on your back button and release it, your focus won’t change until you press the button again. This is something that I use a lot with my recent self-portrait project.
Let’s look at this image of my sons and me:
I placed my camera on a tripod in front of my bed. I asked my sons to sit on the bed, and used them as targets to meter and focus. Once my exposure and focus settled, I didn’t touch my camera anymore. I joined them on the bed (making sure I was standing close to the focal plane they were in when I focused), and the only thing I had to do is snuggle with them and snap away with my remote. We took a series of 10 images without having to care about anything else than having fun, my focus was locked so I knew it would remain faithfully where I wanted it to be!
How do I start?
How to set BBF depends on your camera, so check your user manual.
On my Canon 5D Mark II menu, it is found in custom function IV (C.FnIV), and I selected the 3rd option (AE Lock/Metering + AF start).
If you are a Nikon user, you should go into your custom settings menu, select A (autofocus), select A5 (AF Activation) and then choose AF-ON only.
For those of you already using BBF and loving it, please share your settings in the comment section of this article to help new users find the right path!
So, now it’s your turn! Switch to BBF and play to your heart’s content. You might need a few days to get used to it, but soon enough you will wonder how you could live without it! I swear it’s worth trying because I’ve been nailing my focus ever since I discovered it.
Happy BBF!
Lisa Tichané, France
CM Mentor
Website | Blog | Facebook | Pinterest | Mentoring | Ask a Pro
Maybe it’s because she’s “a bit silly” or maybe it has to do with her being “a child at heart” but Lisa has an incredible talent for photographing babies and children in her fun, clean and playful style with her Canon 5d mark ii, 50 f/1.4, 24-70L and 135L. Marseille, France is the place she calls home along with her two boys where they love to play in the countryside treasure hunting and inventing goofy games. She does enjoy some quiet once in a while where she can browse the web with her coffee and chocolate. Laughter is a must have, though, as she states, “a day without a good laugh is definitely a lost one for me.”
Read more photography tutorials by Lisa Tichané.
This is such a great explanation. I’ve been using this on a 5d Mark II for about 6 months and love the BFF. It took a week to get used to it but I swear by it now. Thanks for the great article!
I’ve been meaning to try this…I’ve read a bunch of explanations BBF and yours was by far the best. I better attend one of you Breakouts! Thank you! :)
I don’t catch it.
What’s the advantade of BBF in the first example (children running towards camera) if you set the AI servo option?? AI Servo runs while you press half way the shutter button; and when you get the moment, you just have to press it a second time. This way you have not to manage TWO buttons…
Hi Jorge. The advantage of BBF here is that you focus and press the shutter simultaneously, therefore ensuring the most perfect focus possible. If you do it the way you suggest, there is a very small delay between the moment you focus and the moment you press the shutter. If your focal plane is shallow (if you use a large aperture, for example), this small moment can be long enough for your subject to step out of the focal plane.
Hope that helps!
Assuming you have focusing set to the shutter button I think AI Servo focuses all the time even if you press the shutter button all the way down. At least in continuos shooting mode so why not in single shot mode as well. So BBF doesn’t offer any real advantage in this situation.
The thing that I don’t understand about BBF is that using it for portraits. Let say if you are using a fast prime indoor with aperture wide opened at F/1.4 or F/1.8. The DOF will probably be probably be anywhere from 1/2 inch or at most an inch. In your last example, self-portrait with your two sons, will not any movement, like snuggling with your sons and having fun with them, move the subjects out of focus? Or if you hand held the camera and use BBF, will not recomposing in between shots also move the subjects out of focus? How is it possible to use wide open prime and BBF without changing the distance between the object and the camera while recomposing? Thank you!
When handholding your camera, you can keep your BBF pressed the whole time, thus re-focusing every time you move your frame. That way, your focus will always be acurate. If you shoot wide open, I would suggest toggling your focal points, in order to be sure that the active focal point will be placed on the eye of your subject when you press your BBF and shutter.
Regarding the self-portrait issue, you are absolutely right, the slightest movement can result in an OOF image. Which is why I would not recommend using a very wide aperture for self-portraits, unless you are sure that your subject(s) will stay still. I always use the smallest aperture possible (given the lighting situation I am in) and crank my ISO if necessary to get the widest depth of field possible.
Hope that helps.
Thank you so much, Lisa! That answered my question. When you said, “When handholding your camera, you can keep your BBF pressed the whole time, thus re-focusing every time you move your frame,” do you mean that you select AI Servo? Else why would the camera re-focus every time you move your frame? If you select one-shot, the focus should be lock when you press BBF.
Thanks so much for this article. I use BBF and love it, but I never used the AIServo setting. Looking forward to using it with active toddlers.
Hi! Your tutorials are great! Do you have some advice for lenses and settings to use with birth photography. I have a Nikon D90 and several lenses but am quite a beginner with manual settings. I took a beginner workshop and learned to take off AUTO and work in Program mode, but when I arrived at the birth i could not get the shutter speed right with the lighting and ended up shooting in Auto most of the time to get the shots I wanted ( there a no second chances!) , but had to use a flash which I don’t want to do. Also the type of focus was off a few times even though i thought i had that set right not to focus on the closest object.
Ugh. Its easy to take great images of birth, i have been doing it for years with a point and shoot, but I need to learn to get this camera off of AUTO now!
Suggestions for a beginner??
Hi LeeAnne!
Birth photography often means to deal with low light situation, so I would definitely recommend a prime lens (50mm or 35mm) in order to be able to use wide apertures if the light is missing.
To learn how to really take control of your camera, I would highly recommend Lynne Rigby’s 101 class. It’s simply amazing! You will learn everything you need to know to shoot in manual mode, and will get out of this workshop feeling empowered! Here is the link if you want to check it out:
http://www.clickinmoms.com/cmu/archives/listing/shooting-101-the-best-darn-beginner-course-ever
Hi, LeeAnne, what lenses do you already have? For indoor, low light setting, it helps to have fast prime lenses like F/1.2, F/1.4, F/1.8, or F/2. You may also want to bump up your ISO to allow you to use slower shutter speed. You have to be careful to make sure the DOF is wide enough since if you set it too narrow, it is easy to get blurry shots with all the actions and commotions.
Ok, now I get it! Very very interesting trick!
Thank U, Lisa!!
Brilliant! Will try it tonight. Great post!
I have four boys. Think it’ll be useful? ;)
I finally get this – thank you!
I am having the hardest time with the bff.. I am a nikon user and for the life of me I cant figure this out. Am I supposed to keep my finger on the bff the whole time? Because when I take it off it is not working like it did.. I am at a loss. I really want to learn BBF but this is causing me to go back to shooting the other way since I can not get a handle on it.
I’ve read this article once before, but read it again just now and decided to give it a try. I’m really excited to see how well I’m able to adjust to using this method with actual people (my daughter is napping right now, which is why I have time to learn!), but I really do think it’s going to change the way I shoot. I shoot a lot of moving babies with my business, so hope BBF will help me keep them in focus better (I used to be a focus and recompose shooter – which obviously doesn’t work well with anything but a still subject).
I have a D600 and this article helped me get it set up: http://www.flickr.com/groups/d600club/discuss/72157631958556973/
There’s a video listed in that article that helps explain the how and why of BBF too (useful for visual learners like myself!): http://www.youtube.com/watch?v=WyPv1bLkwqA
Thanks for a great article!! – Erika
OK, I’m using a Rebel T4i and I have my AI Servo set, I found the custom functions in my menu and have it set on 1:AE Lock/AF. When I depress the shutter half way it no longer focuses so I think my settings are okay – but when I press the AF button or the Star button, I can toggle my points, but the lens doesn’t focus. WHat am I doing wrong? I feel like I’m just missing one step to start figuring this out, but am at a loss?
Hi Melissa! Have you double checked your camera manual to see if you have it set up correctly? If so, I would do a google search to see if someone else has had the same trouble or perhaps call Canon to see if they can help you.
We did some digging, Melissa, and this is what we found…
“how to turn back button focusing on your Canon T4i (650D)
Press Menu
Navigate to last yellow page (Wrench 4)
Select Custom Functions (C.Fn)
Navigate to C.Fn IV Operations/Other – Shutter/AE Lock button [6]
Select Option 3: AE/AF, no AE lock
This turns the * button into the focus button and the shutter button just meters and take the photo.”
Thanks for this great tutorial. If I use bbf do I still use the shutter to spot meter or is this tied to bbf? I have not been able to figure this out. I have a Nikon d7000. Thanks!
Thank you so much for sharing. Great tip. I use AI Servo all the time but never thought to use it in conjunction with the BBF. I am sure it will become my BFF! :)
Hello,
I have my Nikon D800 set up to use the AE button with AF-C This way I get the best of both worlds. Focus and release for a stationary shot or hold AE when tracking a moving subject. You mentioned that you took a self portrait this way. How did you do it? also what happens when I use a cable release or a pocket wizard for a remote shot? thanks in advance!