Face Detection AF
This popular camera focus option is a form of automatic AF point selection found on most compact and compact system cameras – and even some SLRs in Live View mode (when the image is composed on screen).
It works by recognising face shapes in the scene and then prioritising the focus towards them.
Refinements on this camera focus system include Smile Shutter, which triggers the shutter to fire when the camera detects that the subject is smiling (it doesn’t work with every smile, but it can be very effective).
Some cameras can also be set to recognise particular faces in a crowd and focus on them. This is a very useful option for photographing your children at parties or events when they are surrounded by other kids.
When Face Detection AF is activated you’ll notice boxes appearing around peoples’ faces on the camera’s LCD to show that they have been recognised. Half-pressing the shutter release brings the faces into focus ready for the shot to be taken.
As you might imagine, Face Detection AF is extremely useful at parties and social gatherings when you want to get lots of people pictures.
Focus and recompose technique
Although most digital cameras offer a collection of AF points so that you can select the one that sits over your subject, there may not always be one exactly where you need it.
In these instances the camera ‘focus and recompose’ technique comes in very handy – and it can be quicker than selecting an AF point even if there is one over your subject.
Imagine, for example, that the central AF point is selected, but your subject is off to one side of the frame. All you need to do is move the camera so that the AF point is over the subject and half-press the shutter button so that the lens focuses.
Now, with the shutter button still half-pressed to keep the focus locked, recompose the image so that the subject is where you want it in the frame and press the shutter release home to take the shot.
This also a useful focus technique to use in low light, as the outer AF points tend to be less sensitive than the central one.
When using this camera focus technique, it is essential that the camera is set to single AF mode.
If it is set to continuous AF, the camera will refocus the lens on whatever subject is under the active AF point when you recompose the image.
PAGE 1: Manual Focus, Single AF, Continuous AF
PAGE 2: Automatic focus point selection, Manual focus point selection
PAGE 3: Face Detection AF, Focus and re-compose technique
PAGE 4: Back button focusing, Hyperfocal distance focusing, Focus stacking