"Invisible flash" could eliminate bright camera bulb pops

Smile, you're on not-so-candid camera.

The bright and sudden pop of a flash bulb means photos are being snapped, and while it's (arguably) fun to have your picture taken, the harsh glare of a flash bulb often leaves subjects squinting and annoyed.

But what else can you do if natural light isn't an option?

Enter the so-called "invisible flash" or "dark flash," which utilizes light waves outside the visible spectrum to illuminate your subject. Infrared and ultraviolet light is pulsed, with visible light frequencies filtered out, and a special camera sensor captures the invisible-to-the-naked-eye frequencies to create a finished image.

The resulting image isn't perfect -- the pictures are described as having the character of night-vision shots --so the new system, developed by two researchers at New York University, grabs color information from a flash-free picture which is snapped after the UV-illuminated shot is taken. Detail from the first shot and color data from the second are then combined in software, with what is called a "remarkably natural end result."

The system isn't perfect. Not all objects reflect UV or IR light, so the camera can't pick them up properly. The New Scientist story linked above notes that freckles present a particular challenge for the system. (I guess that's one way to clear up your skin in photographs, without resorting to Photoshop.)

Still, the prospect of taking shots in low light without the harsh glare and distraction of a flash bulb pop is a tantalizing one, even if the results are imperfect. The paparazzi, renowned for sneaky night-time shots, must be positively drooling over the possibility.