The Palazzo Vecchio in Florence, Italy
What’s the News: The walls of the Palazzo Vecchio, the centuries-old seat of Florentine government, have doubtless housed many secrets over the years. Now, a physicist, a photographer, and a researcher who uses advanced technology to analyze art are teaming up to reveal one secret that may still linger there: a long-lost mural by Leonardo da Vinci, thought to be hidden behind a more recent fresco. The team plans to use specially designed cameras, based on nuclear physics, to peer behind the fresco and determine whether the da Vinci is actually there—and if so, to take a picture of it.
What’s the News: Lytro, a Silicon Valley start-up, has designed a camera that lets you shoot first and focus later. The camera captures the far more light and data than traditional models, and comes with software that lets you focus the photo, shift perspective, or go 3D after you’ve taken the photo. The company plans to sell a consumer, fits-in-your-pocket model by the end of the year.
The camera works by bouncing ultra-short bursts of laser light off a solid surface (like a floor or an open door). Most of the light is reflected back to the camera, but some scatters in every direction, a small portion of which then hits and bounces off the object to be visualized (and other parts of the scene). Some of that scattered light then bounces back off the door or floor, and finally make its way back to the camera.
“It’s like having x-ray vision without the x-rays,” said Professor Ramesh Raskar, head of the Camera Culture group at the MIT Media Lab and one of the team behind the system. “But we’re going around the problem rather than going through it.” [BBC News]
The team’s computer program can analyze the scattered light and re-create a picture of what is lurking around the corner. The secret to the technology is to not overwhelm the camera’s sensors with the initial reflection from the door. The camera’s shutter has to wait until this initial pulse has passed before trying to collect the light bouncing around.
The camera notes the arrival time and intensity of each photon of light to build a three dimensional picture of what it can’t actually see. It takes several passes of the scene to build a full picture.
Optics researchers have invented a camera that uses infrared lasers to bounce light off an object, and say the result should leave shutterbugs with a serious case of technology envy. Their device can take 6.1 million pictures in a single second, at a shutter speed of 440 trillionths of a second. Light itself moves just a fraction of a centimeter in that time…. “It’s the world’s fastest camera” [Wired], says study coauthor Keisuke Goda.
Conventional digital cameras use charge-coupled devices (CCDs) to take a picture. The devices contain semiconducting chips that … produce electrons in response to light. The electrons are read off the chip and their signals are then electronically amplified and encoded as a digital image [Nature News]. But that process has its limits. Top-notch conventional cameras top out at about 30 frames per second, while the fanciest scientific instruments can take about one million frames per second. For Goda and his colleagues, that just wasn’t fast enough.