Our cameras convert light into electrons, then we count the electrons to see how much light there was. But what if you could just trap the light and hold it?
For several decades, a number of researchers have been trying to do just that. Before the turn of the century we were able to slow light. Not too many years later we started seeing the first claims of stopping light, though not for very long. Last week the University of Darmstadt published a paper showing how they stopped light for one minute. The previous top claim I'm aware of was 16 seconds (Georgia Institute of Technology).
Think about it. The fastest thing we know of, light, totally stopped in its tracks, held captive by a crystal. Oh, you want the technical details. How about a simplified explanation everyone should be able to understand instead? You create a crystal-based substance that turns opaque except when triggered by something (in this case a laser). You trigger the "transparency mode" and send your light into the substance, but before it gets through you turn off the transparency. The atoms within the crystal take on the energy from the photons. When you make the crystal transparent again, the atoms lose the energy back into photons and the light continues on its merry way.
Now I can't help but go all Jules Verne or Philip K. Dick on such research ideas. For example: I could go out and "take pictures" today, but wait for years for a "better sensor" to be developed! Wow, the pixel peepers will get all excited about that: how good does the sensor have to get before it's worth emptying the light container? Or how about this one: is a species actually extinct if the light reflection from the last living individual is still held in suspension? After all, you could still see the last living animal if you just open the container. If we can stop light in continuous sequences (e.g. video) we'd be doing more than just preserving a moment forever, but completely delaying our observation of time itself. And SD cards? Thing of the past, right?
I'll keep the good parts of my imagination on this subject private for the time being. The old Sci Fi short story part of me wants to take a crack at this one.