Using Back Button Focus In Motorsport Photography
Now in motorsport, there is the added challenge the subject can be travelling at in excess of 300km/h, which is even a test for the best autofocus systems in the world’s premium sports cameras on the market.
So how do you make sure your photos from on track are in focus?
The best tool available on modern cameras is separating the focus button from the shutter button and that’s where back button focusing comes into it.
By default, all digital cameras are setup with a half press off the shutter button to focus before a full press to take the actual photo. No doubt something you are very familiar with.
However, in DLSR and Mirrorless cameras you can change the button configuration to use one on the back of the camera to focus. This method is known as back button focus.
So what is back button focus specifically?
Back button focus is a simple technique that separates the focusing from the shutter, so you are able to apply them individually.
This is achieved by changing the settings in your camera and allocating the autofocus function to a separate button on the back of the camera.
Some cameras have a designated button for this feature enable this, notably the AF ON button on Canon and Nikon cameras. In other manufacturers cameras, you can replace the function of another button with autofocus.
But what is the problem with having the shutter button do both jobs?
There are a number of reasons to change this, firstly being able to pre-focus.
In motorsport things happen quick. Really quick! To maximise your potential to get sharp in focus shots of a particular section of the track you can pre-focus so the camera doesn’t need to hunt to find the target.
Secondly, there are times where we don’t want the camera to be adjusting focus. Particularly while taking panning shots if you have focus set-up in AI-Servo mode (that’s a whole article for another time).
While panning, pre-focus on a particular area of the track and then bring your attention to using a smooth motion to get clean crisp shots. Not bumping around the camera pushing different buttons.
This is becoming less of an issue as the latest mirrorless camera offer nearly 100% focus coverage. But on DSLRs – even the top tier ones – focus points were heavily centred in the middle of the frame. And in motorsport photography, we rarely want the subject of out photo dead centred in the frame.
Are there any drawbacks to using back button focus?
Switching to back button focus takes a little getting used to. So, I have it set up on all of my cameras. Even ones I wouldn’t necessarily use at the track. It’s a rhythm and feel thing.
In fact, these days if someone hands me their camera it takes me a couple of seconds to remember the regular way of using the auto-focus.
So, if you don’t get it straight away never get too concerned. It will take a bit of practice until it becomes natural.
Just make sure that you give yourself time to adjust that won’t impact on paid gigs.
Check out these deal from our supporters:
I've been working as a motorsport photographer in Australia since 2012, building up my business InSyde Media. I am very fortunate that I have been able to work at all sorts of motorsport events including Supercars, F1 and WRC all over Australia and New Zealand. Also, check out my personal website where I document my travels and a few other things.