Lytro Sheds Some Light On Light Field Photography

How does it work?

The secret behind the Lytro camera is something called light field technology. The camera has a small light field sensor inside of it, allowing it to capture a light field, which, as Lytro defines it, is "the amount of light traveling in every direction through every point in space." So whereas typical cameras can only capture the intensity and color of these rays of light (creating pixels), the Lytro camera also captures the vector direction of the rays of light.

"When a camera captures the direction in addition to the intensity and color of light, it's no longer capturing a pixel, it's capturing a ray," said marketing manager Gretchen Harding. As such, there aren't any existing terms from current photo technology to describe this camera's "resolution," so Lytro created its own unit of measure: the camera's light field sensor captures 11 megarays, or 11 million rays of light.

But the light field sensor isn't the only star of the show. There is also a small light field engine (version 1.0) found inside the Lytro camera, which takes over after the light rays are captured. The light field engine is powerful software that processes the light fields and subsequently creates interactive pictures in which users can adjust the focal points right on the camera. With all of the directional information from the light field, different focal points can be achieved by switching to the various locations in which any two of the light field's rays intersect.

"It's all computational photography," explained Lytro's director of photography, Eric Cheng. He pointed out that there is also a more advanced version of the light field engine software found in the Lytro camera's bundled editing software, which is why users are also able to adjust their "living pictures" on their computers, too.

Getting to know the Lytro camera

The Lytro camera has a very unique build, as far as cameras go: It's a rectangular tube that's 4.41 inches long and 1.61 inches wide. It's a little heavier than you may think at first, weighing in at 7.55 ounces, but it's certainly nothing unmanageable. Thanks to a grippy rubber material coating the back third or so of the camera, the Lytro is actually quite comfortable to hold despite its edges and literally boxy form factor. Its design is also quite minimalist, with only two buttons -- power and shutter -- and a single micro USB port located on the underside of the unit.

In terms of the hardware, the light field sensor is CMOS, bound with a micro lens array and is roughly the size of a Point and Shoot camera's sensor, according to Cheng. It has a constant aperture with an f/2 lens and sports an 8x optical zoom that can be surprisingly noisy as the gears whir and click under the hood. I did appreciate how the zoom controls were implemented, however: there is a capacitive touch surface on the top of the camera (towards the back on the rubberized surface) that you simply drag your finger over left and right to zoom in and out. Unfortunately, the Lytro does not come equipped with a flash.

The back end of the Lytro is where users will find its 1.46-inch LCD touchscreen display, which serves as another form of input beyond the physical shutter button on the top of the camera. With the touchscreen, users can tap different areas to spot meter or select focal points (whether in real-time or playback mode) or access the camera's menus.

The actual interface of the camera is simple, due mostly to the fact that it doesn't have a ton of features. When in standby, nothing is on the HUD -- which is probably for the best given the limited real estate -- unless you're zooming, in which case a zoom bar pops up along the top edge of the screen. If you want to see the handful of options that the camera has available, you just swipe upwards from the bottom edge of the screen, which pulls up a small toolbar with three buttons: one for playback, one to view the remaining amount of storage, and one for switching to Creative Mode.

Creative Mode allows users to choose the center of the camera's refocusable range, so one instance in which this could be used is if you want the range to be on a person's face from their nose to their ears, but nowhere beyond that. All you need to do is tap the touchscreen to indicate where you want the range to be centered. Creative Mode can also let you shoot an "all focus" shot, which Harding said can come in handy as a sort of Macro Mode for close-range shots. But for those who are wondering, when shooting outside of Creative Mode and taking a full-wide shot (shooting with no zoom), the focus range of the Lytro goes from roughly 4 or 5 inches to infinity.

So how was it?

It's difficult to deny that the Lytro camera is a fascinating piece of technology, but after spending some time with it, I found that a certain amount of care needs to be taken when shooting photos in order to enjoy the benefits of light field photography. As Harding pointed out, shooting carelessly "is never going to yield an interesting picture. It's not a magic camera."

Zooming was especially crucial for creating the necessary shallow depth of field, which, as Cheng explained, was very important in light field photography. If I was shooting at full wide angle, I found that only images with severely dramatic differences in depth -- like having my finger a matter of inches away from the lens with the rest of the scene behind it -- could produce notable shifts in focus when toying with them after the fact. If there were, say, two signs, one of which was four or five feet behind the other, but they were both 25 feet away from me, it was necessary for me to zoom in closer to achieve a better focus.

Also, with a screen that's less than 1.5 inches in size, I did not find the camera to be an ideal place to enjoy the spoils of light field photography. You could barely make out adjustments in focus -- again, unless it was something very dramatic like the finger example -- much less the finer details of a photo. Granted, you can double-tap the screen to zoom in and see the photo in better detail, but it's still not ideal as the resolution isn't that sharp and you have to drag your finger around to see other parts of the picture when you're zoomed in. It's all just a little claustrophobic, and that's the last thing I want when trying to explore something as remarkable as light field technology. But that's where the software and post-production come in.