Why do I use Back Button Focus?

I have been taking photographs for many many years now and I steered clear of using back button focus (Canon) for a few reasons. 

Reason number 1 – Getting out of my comfort zone

I was comfortable using the main focus and image capture button on the front of my camera. I had been taking photographs this way for years and it had served me well. As my mum always said, “why change something if it ain’t broken?”

Reason number 2 – Why risk a loss of quality

Even if I say so myself there wasn’t a lot wrong with the images I was taking. I couldn’t actually see a good reason to change from front to back button focusing.

Reason number 3 – Why bother changing

I hate change for the sake of change. I had been getting flack from my peers for quite some time before I bit the bullet. But honestly, I couldn’t see the benefit of trying to learn something new when I was getting good results anyway.

Reason number 4 – I couldn’t be bothered!

This is the real reason if i’m being honest. To my mind it was effort, (omg I sound like my boys!) No-one had actually given me a good enough reason to go through the pain of learning a new technique.

Back Button Focus, a Revelation

To all of you out there who are thinking about swapping to bbf, do it! Eventually I took the plunge and set my camera up so that one of the buttons on the rear of my Canon 7d mkii camera body acted as the focus button. 

As you can see in the image above my AF-ON button now acts as my back focus button.

The Advantages of Using Back Button Focus (Canon)

So, lets get down to it.

What Exactly is Back Button Focus?

Within your cameraโ€™s menu settings, you have the ability to assign certain functions to different buttons on your camera. With most DSLR cameras, by default, you half press the shutter button down to set the focus. In this article, I try to explain why I changed to back button focus, and the benefits of assigning focusing to one of the rear buttons instead of using the shutter button.

Back Button Focus simply changes the method of by which you focus the camera on your subject. It simply means that your index finger is now solely responsible for releasing the shutter, and your thumb is now responsible for focus.

Is it easier? Probably not, so why bother?

Like everything new it takes a bit of getting used to. And, if I’m being perfectly honest, it makes my thumb ache after a while. But that being said I wouldn’t go back to using the shutter button for focusing. The set up is reasonably easy and once you have got some muscle memory it’s no more difficult to master than keeping both eyes open. You do don’t you?

Why Should you Bother Using BBF?

There are a few reasons why I prefer to use Back Button Focus over focusing with the shutter button. (BTW, I cover this technique in my ‘Develop Your Photography Skills‘ workshop.)

1. Your Focus will Hold (even if you release the shutter button).

When you remove the focusing function from the shutter button, you no longer need to worry about losing focus on your subject.

How many times have you focused a shot, lifted your finger off the shutter button accidentally and had the camera totally focused on the wrong thing when you re-press the shutter button. Yep, me too ๐Ÿ™

And, how many times have you taken a totally useless burst because you pressed a little bit too hard on the shutter button.

Setting up your camera so that the focusing function is accessed by a totally different button allows the shutter button to be responsible for releasing the shutter, and nothing else.

What’s the Big Deal with BBF?

Changing the way you focus may not seem like much of a game-changer, but as a wildlife photographer attempting to capture potentially fast and erratic subjects, it makes my life so much easier.

I use the Canon 7D Mkii, (the perfect wildlife camera in my opinion), an I face this problem all the time. Moving away from the shutter button to focus, to back focusing makes my life so much easier. The 7D Mkii comes with fantastic auto-focus capability. Combine that with back button focus (Canon) and voila, I am able to track fast moving raptors with relative ease. Once the focus has achieved a lock I can concentrate solely on capturing the shot or a burst.

Even if the subject is obliging and sits still for a few seconds, BBF still wins because it allows me to focus, RELEASE the button, RE-FRAME and then take the shot. Which is exactly what I did with the Kingfisher below. Let me repeat that, I can focus using the back button, then if I release it, I can re-frame my subject at my leisure. This saves me so many pixels in post production because I do not have to crop the image to position the subject.

2. Focus and Re-Frame

Like every good photographer I try to adhere to the rule of thirds. However, sometimes the action happens so fast it isn’t at the top of your priority list. However, as with the Kingfisher image above, I was able to get focus and re-frame. The important thing to note here is that I already had several shots with the bird incorrectly positioned in the frame before I released the back button and re-positioned the camera.

Why is the ability to re-compose the image at time of shooting, so important?

My camera is a crop sensor which means it has a smaller sensor and therefore less real estate when it comes to pixels. As I print a lot of my images at very large print sizes for clients and customers I need every single pixel I can get.

Let me explain with a visual example.

With this image of an Eagle Owl I was working quickly and was unable to frame it exactly as I would have liked. As a RAW file it imported into Lightroom at 5472 x 3648 pixels.

eagle owl uncropped

In order to frame it correctly I had to use the crop tool. The image then looked like the one below. Even then I wasn’t totally happy with the framing, (but that’s post another topic altogether!)

The point I am trying to make is that my image is now only 4097 x 3277 pixels. So what I hear you say. I have just lost the ability to print this out at the larger print sizes my clients sometimes ask for.

eagle owl cropped

Will this affect my image when I post it on my website, or Facebook or Instagram? No not really, but that’s not the point I am trying to make though is it.

I can almost hear some of you telling me that I could bypass this by locking focus, then switching the camera lens into manual focus, but locking focus on the camera and switching your camera lens into manual focus is a sure way to never consistently capture a fast moving subject.

Some of you are yelling that the manual way to focus and recompose should be avoided and that you should just toggle your focus point. True, and I toggle my manual focus point in some situations. However, single point focus gets me the best results so that is what I personally use.

Like everything else we all have different preferences, a different way of doing things which suit our style. Personally I wouldn’t go back to front focus but I totally respect your decision not to go for BBF as well.

I hope you found this article interesting and thought provoking. Hopefully I have convinced you to give BBF a try, even if you don’t stick with it. In any case if you enjoyed reading this please leave me a comment below, I always appreciate hearing your thoughts. ๐Ÿ™‚

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