5
Mastering Autofocus Options

One of the most useful and powerful features of modern digital cameras is their ability to lock in sharp focus faster than the blink of an eye. Sometimes. Although autofocus has been with us for more than 20 years, it continues to be problematic. While vendors like Sony are giving us faster and more precise autofocus systems—like the full-time autofocus possible with the SLT series’ translucent mirror technology—it’s common for the sheer number of options to confuse even the most advanced photographers.

One key problem is that the camera doesn’t really know, for certain, what subject you want to be in sharp focus. It may select an object and lock in focus with lightning speed—even though the subject is not the one that’s the center of interest of your photograph. Or, the camera may lock focus too soon, or too late. This chapter will help you choose the options available with your Sony SLT-A77 that will help the camera understand what you want to focus on, when, and maybe even why.