By SAM GROBART - NY Times – Gadgetwise – February 29, 2012, 5:00 pm
But what if you could take a picture and refocus it after you had taken it? What if, just by clicking around a photo on your computer screen, you could choose which part of the image should be clear and which part should be blurry?
You can with a new camera called Lytro, and it’s astonishing. With a Lytro, you take a picture as you would with any camera, but the digital file it creates can be refocused after the fact.
This is fairly mind-blowing. Imagine a wedding photo with the bride in the foreground and the wedding party in the background. Click on the bride, and she’s in focus while the bridesmaids are blurry. Click on the groomsmen and the focus shifts to them. Do this over and over all around the frame — the picture readjusts on the fly, smoothly moving from one focal point to another.
The effect makes photography almost like cinematography, revealing things vividly in the foreground and background. Refocusing a Lytro image, I felt like one of those C.I.A. agents in the movies who is looking at satellite images and asks some technician to “enhance” the picture until Carlos the Jackal comes into focus.
The Lytro, which began shipping from lytro.com on Wednesday, can do this because its image sensor captures more data than your standard camera does. Not only does Lytro’s sensor register the usual things — like how bright the incoming light was and what colors it contained — it also knows which direction the light came from. Armed with that information — known among scientists as light-field data — the Lytro’s onboard software can create multiple focal points. A view of the Lytro’s inner workings shows how this array of tiny lenses and microprocessors makes this happen.