Goat in a Doorway
Back Button Focus
Have you ever been doing the half press to focus on your shutter while focusing your camera, and then wanted to move the subject a bit, but you get the focus, move and then because your finger lifted, you’re now focusing on the wall behind the subject instead of on the subject itself? I see this all the time, and have a simple solution.
It’s called back button focus.
With back button focus, you commit one of the buttons on the back of your camera – on my Nikons I prefer to use the AF-ON button – to being the focus button, meaning that the shutter button then does only one thing, it release the shutter. Follow my thinking on this and you’ll see the advantages:
1. By separating the focus from the shutter, you can use the Back Button to focus and then lift your finger from it. As long as you don’t touch it again, anything in that plane of focus will remain in focus. You can then move the camera to any composition you like, and the subject will remain in focus, as long as it doesn’t move. Great for focusing on a landscape feature and then recomposing.
2. Back button focus also allows for fine tuning your focus between manual and auto focus, as once that button is set, it doesn’t change, unless of course you go and rotate the focus ring on your lens yourself. Pro lenses often have a manual ability to focus (in Nikon parlance, S series lens do this), which is super, particularly for Macro photography.
3. Finally, I find that having used BBF for a number of years, it is faster for me then using the half shutter deal, because I can usually pre-focus on where the action I’m expecting will take place (like the doorway wehre the goat is standing in the picture above), and if I’m off, I simply hit the back button again and I’m in business.
So, why not look through your manual or google your camera online and find out if you can do back button focus, and then give it a try. Once you do this, I suspect you won’t go back…
BBF great for close-ups and macro
Focus and then Compose
Fast enough to Focus on Birds - or where they are sitting!
Perfect focus on foliage and the trees behind
