So we get excited by cameras that have burst speeds of 60 frames per second at a resolution of three megapixels. How about a camera that can shoot a trillion frames per second? That's fast enough to capture a burst of light travelling through a Coke bottle, bouncing off of the cap, and reflecting back into the bottom. In slow motion.
It's something that Andreas Velten, Professor Ramesh Raskar, and Professor Moungi Bawendi have been working on at MIT.
Problem is, apart from costing $250,000, it also takes about an hour for the camera to capture a sequence of events that takes, ooh, about a nanosecond.
The camera that they use is a streak camera. Its aperture is a narrow slit; photons pass through it and through an electric field that deflects them in a direction that's perpendicular to the slit. Later-arriving photons are deflected more than earlier-arriving ones. But this means that the two dimensions in which it captures images aren't both spatial; one is spatial (the one corresponding to the direction of the slit) and the other (corresponding to the degree of deflection) is temporal.
So that it can record that beam of light in the coke bottle in a format that we'd recognise as 2D, the sequence has to be recorded again, and again, and again. Each time, the camera has to be moved slightly so that a 2D image can be constructed. That, of course, means that it isn't exactly useful for anything that isn't perfectly repeatable. And hence the moniker 'the world's slowest fastest camera.'
It might have the ability to make anything in the universe look slow, but it takes a while to manage it!
For scientists, the streak camera can record light passing through or being emitted by a chemical sample. But what about practical uses for photographers? One day, it might be at the foundation of developing better flashes. As Professor Raskar put it: 'With our ultrafast imaging, we can actually analyse how the photons are travelling through the world. And then we can recreate a new photo by creating the illusion that the photons started somewhere else.'