Vote 2020 graphic
Everything you need to know about and expect during
the most important election of our lifetimes

Physicists Figure Out How to Take Photographs In Near-Total Darkness

Illustration for article titled Physicists Figure Out How to Take Photographs In Near-Total Darkness

Tens of thousands of photons go into making up each pixel in your standard cat photo. That's because existing cameras—even infrared night-vision ones—rely on many, many photons of light to create an image. But now physicists have photographed in almost pitch blackness, where there on average is less than one photon of light per pixel.

Advertisement

It's a remarkable bit of technical achievement, and it has it has pretty obvious spycraft applications. The key, as the Physics ArXiv Blog lays out, is combining two cutting-edge imaging techniques.

The first is about timing the photograph at the exact instant a photon hits the camera. This is done through heralded imaging with a pair of entangled photons. One photon acts as a trigger to announce the arrival of the other photon, which is used to make the image.

Advertisement

A second technique, called compressed sensing, optimizes the raw image. You can see the effects of the transformed image of a USAF resolution target (right) below. Since the properties of a pixel in an image tend to follow a known statistical distribution, we can extrapolate an image from just a small number of data points using some math. In the 300x300 pixel photograph of a USAF resolution target, an identifiable image emerges at about 7000 photons, or less than 0.2 photons per pixel.

Illustration for article titled Physicists Figure Out How to Take Photographs In Near-Total Darkness

Aside from spying in the dark, this technique could also have applications in biology. Photons can damage certain delicate samples as they pass through them. The less light, the better. We're pushing against the limits of photography here. [The Physics ArXiv Blog, ArXiv]

Share This Story

Get our newsletter

DISCUSSION

Ginseng108
Ginseng108

Interesting stuff. Physics = fascinating.

On a more practical note, taking photos of relatively still subjects with my iPhone is not an uncommon situation (e.g., that cool moose head in a dim dark tavern). To get full resolution shots with nearly imperceptible grain, I've been using Cortex Camera for iOS.

I have 12 photo apps on my iP5 and the two I use the most are the built-in cam and Cortex. The results can be very dramatic.