With the focus locked you can now recompose your shot before taking the final photo. In our example image, we’d bring the camera back to the composition we want and press the shutter button down fully. This would leave us with the same picture before, but with the woman rather than the background in focus.
This sort of focus lock is quick and easy to use, and gives you a lot of flexibility without having to mess around with settings like autofocus points. However, it only lasts for one shot – as soon as you take a photo the focus is lost and you need to repeat the process. If you’d like to re-use your focus point for many shots, you can use the next method.