Game-changing camera focuses after the fact

SAN FRANCISCO — It’s the photographer’s nightmare. You’ve taken the perfect photo of your daughter holding a ball. But you focused on the wrong thing. The ball is sharp, the girl blurry.

Now imagine being able to refocus the entire photo — after the fact.

That’s the awesome thing about the Lytro, the first consumer camera to employ a technology called light-field photography that until now was the province of scientific laboratories.

Launched by a Mountain View, Calif., start up to capitalize on research conducted at Stanford University, the Lytro introduces the concept of a living photo that can be adjusted on the fly by photographer and viewer alike.

Unlike a traditional digital camera, which depends on light directly hitting a sensor, the Lytro captures all the light in a scene traveling in any direction — enough information to allow the focus to be manipulated in any number of ways. Conventional camera-makers talk about megapixels, the number of dots of information that make up an image; Lytro talks in terms of megarays to describe the amount of light captured. The Lytro claims a rating of 11 megarays, or 11 million rays.

If the technology is unfamiliar and exotic, the Lytro itself, mercifully, isn’t. For all its sophistication, it’s is a pleasure to use. Not having to focus makes it easier than traditional point-and-shoot cameras, or even your smartphone. The Lytro turns on instantly and there’s no shutter lag. My biggest annoyance was a lens cap that kept popping off.

The camera, which fits easily into a jacket pocket, weighs less than eight ounces. A little more than four inches long, it resembles a squared-off spyglass. It’s sold on the Lytro website, which offers two models. The 8-gigabyte version ($399) comes in blue or graphite and can hold about 350 photos. The 16- gig model ($499) is red and holds about 750 photos.

At one end of the aluminum-clad body is the lens; at the other is a 1.46-inch square touch-screen viewfinder. You activate the 8X optical zoom by running your finger back and forth along the rubberized top of the camera; a quick tap of the screen adjusts the exposure. The shutter is an indentation atop the camera, easy to find by touch and hard to hit by accident.

Just how revolutionary the Lytro is doesn’t really become apparent until you connect it to your computer with the included USB cable. As with Cisco’s late, lamented Flip videocam, the desktop software you need is built into the camera and installs itself automatically. At the moment, it only works with Apple’s Mac operating system; a Windows version is on the way.

Your photos are displayed iPhoto-like, but with one big difference: Clicking anywhere on a picture refocuses it on that specific point.

A photo I took of San Francisco Bay from the landmark Ferry Building allows me to choose between focusing on a close-in piece of iron railing or, off in the distance, the Bay Bridge or Yerba Buena Island.

A shot of Rodin’s “Burghers of Calais” on the Stanford campus lets me change which of the burghers I want to emphasize. In a close-up of a flower at a Palo Alto farmers market, I can sharpen the focus on the pistil, or emphasize an individual petal.

Don’t like my choices? If I post my photos to the Lytro website and share a link, anyone viewing them can make his own decision about what to sharpen and what to blur.

At the outset, at least, the website and Facebook will be the only ways to directly share Lytro’s living pictures — a downside if you use some other site, like Yahoo’s Flickr or Google’s Picasa, for your online storage and sharing. Lytro’s software does make it easy to tweet a picture in Twitter or (plus)1 it in Google Plus, but in each case it’s just a link back to the version on Lytro.com

You’ll also find some things missing from the Lytro — a flash, for example, and the ability to shoot video. But it does offer a “creative mode” that gives the photographer more control over a shot’s refocus range, and the company says other capabilities are in the works, including three-dimensional images, light-field editing tools and the ability to make an entire photo in focus.

Introducing consumers to a completely new technology is inherently tricky, but Lytro has done an impressive job of keeping things simple. You don’t have to forget everything you know about point-and-shoot cameras to use it — just the part where you worry about ruining a shot because it’s out of focus.