A View from Tom Simonite
Why You Want a Light Field Camera
Lytro’s technology is never out of focus and allows 3D from a single lens
News of a camera that promises to put an end to unfocussed photos forever broke overnight, as Silicon Valley startup Lytro announced a camera for consumers based on research at Stanford University.
The company is building a “plenoptic” or “light field” camera, which features an array of small lenses between the conventional lens and the sensor. That enables the camera to collect more light, from a wider range of directions than a conventional one. Researchers have been tinkering with the idea for years and shown that the rich information captured that way allows for features cameras don’t have today. Read on for the three main benefits.
Shoot first, focus later
Lytro’s camera will record the light information it collects in a special file format that allows a photographer to choose what depth they want to focus to on their computer. Click on the different things in the photo above to try it.
Lytro’s founder, Ren Ng, modified a professional camera into a plenoptic one while at Stanford. A technical report on the research details that prototype, and explains that because more light is captured images can be clearer under the same conditions. The left and middle images below were taken with an unmodified version of the camera with a small aperture (little light let in; large depth of field) and large aperture (lots of light let in; small depth of field) respectively. The image on the right was taken with the plenoptic version and a large aperture. Lytro claims its camera will be able to take photos in very low light conditions, such as night clubs.
3D from a single lens
Each of the micro-lenses in a plenoptic camera’s array views a scene from a slightly different angle and those views can be compared to deduce the distance to the objects in front of the camera.
Last year Tom Bishop and Paolo Favaro at Heriot-Watt University in Edinburgh, UK, published a method to extract the depth of every pixel in an image from a plenoptic camera. The top image below shows an image taken by a prototype camera they built, and the lower image the depth map extracted from it (bottom). Areas closer to the camera are shaded darker. A depth map can be combined with the color captured by the camera to represent the image in full.
For a casual photographer to make use of such a feature they would require a way to display and view 3-D images, such as the Nintendo 3DS portable gaming console.