A camera that never loses its focus

In 2006, Ren Ng, a graduate student at Stanford, published a doctoral thesis outlining a revolutionary technology in photography that almost seemed like an illusion. You could take a picture of two people, one in the foreground and one in the background, and later switch the focus between the two subjects as if you were directing an art house horror movie. In 2012, Ng's firm, Lytro, introduced its first light-field camera to positive reviews.

This week, Lytro will begin shipping a new camera, the Illum, a big, $1,499 (Rs 90,000) model aimed at serious photographers. While it is possible to take some incredible shots with the Illum, the camera takes some getting used to, and it is not for everyone - probably not even for most professional photographers.

Yet despite its narrow audience, the Illum is still an interesting device because the technology inside it could well have far-reaching implications for photography. If the device sells well and paves the way for Lytro's long-term prosperity, the company's light-field technology could change the way we make movies, improve medical imaging devices, and radically reduce the price of most professional cameras and lenses.

In many ways, Lytro is a testament to the new possibilities for making hardware. Though the company is tiny, with 85 employees, it has managed to cajole some of the world's largest tech suppliers into providing components for its camera.

The Illum has a powerful mobile processor made by Qualcomm, and it includes a lens custom-built to Lytro's specifications. The fast processor enables one of the camera's best features, a system that shows you, in real time, which region of your photo can be refocused.

Yet the Illum also demonstrates the perilous economics of the hardware business. Planning for the Illum began years ago. Ben Horowitz, one of the founders of the venture capital firm Andreessen Horowitz and an investor in Lytro, said in an interview. "Lytro has a very, very big opportunity to change the world, but there ends up being all kinds of challenges along the way. That's because hardware is just hard."

Still, Lytro says the Illum isn't the final embodiment of its technology, but rather one more step along the path toward demonstrating the possibilities of its new kind of photography. In a traditional digital camera, a sensor collects just two data points about the light that hits it: its colour and its brightness. A light-field camera can capture much more data, including information about the direction in which rays of light are travelling through a scene.

This directional data allows a light-field camera to improve performance and cut costs compared with other cameras. For instance, the Illum includes a lens with an extremely wide zoom range - it can shoot from a focal length of 30 millimetres to 250 millimetres - but its maximum aperture remains constant (at f/2.0) over that range.

On a traditional camera, it is just about impossible to find a single lens with such a wide range and a constant aperture. The ones that comes closest, like Canon's f/2.8 lens with a 70-200mm zoom range, have smaller ranges and smaller apertures, and they are much more expensive. The Canon lens sells for $2,499 (Rs 1.5 lakh).

According to Horowitz, Lytro's presales of the Illum have already been brisk. "Based on what they've sold already, it's likely to put us close to break-even for the year," he said. "But in general, there's always this problem with a hardware company. If you build a product that doesn't sell, it's a big problem. Particularly if you make a lot of them."

© 2014 The New York Times