Stay on track

Another must for wildlife is backbutton focusing, which enables you to autofocus with your thumb and release the shutter with your forefinger. This makes it easier to track moving subjects; you simply place your chosen AF point over your subject, hold your thumb down to focus on it, and then track it through the viewfinder until you’re ready to take the shot. In continuous AF mode, as long as your keep your thumb on the AF-ON button, your camera will continually adjust the focus, even if your subject is moving towards or away from you at speed.