How Autofocus Works

THE STORY BEHIND THIS INVALUABLE TECH ONCE CONSIDERED A “GIMMICK”

- Seth Shostak

WHEN, IN 1985, autofocus first made its appearance in a popular SLR, the Minolta Maxxum 7000, I figured it was a gimmick. Hey, I’m a Homo sapien, with an opposable thumb that allows me to focus a lens. To me, any battery-burning technology to take over this task was about as useful as a robot finger to punch the shutter.

Leica had developed autofocus in the 1970s and apparently felt the same way. They reckoned that anyone who could afford one of their cameras knew how to turn the focus ring. So, they sold the technology to Minolta.

Well, I’ve undergone an attitude adjustment. I use autofocus for maybe 70% of my shots, allowing me to shift more of my neural activity to composition.

Sure, there are situations where manual focus is better, just as there are circumstances when you want to choose manual color balance. But autofocus is a genuinely good thing, and you’ll be more interesting at social events if you know how it works.