A Stanford grad student, Ren Ng, recently developed a "plenoptic camera" that allows photos to be focused after they are taken. The camera, whose workings are documented here and here, allows a single snapshot to later be focused at any distance. This struck me as an amazing advancement for designers, as refocusing an image is something I always wish I could do when making a composition. This announcement made me stop and think for a moment about how to further improve the lives of designers. I was eventually reminded of another such process that improves life for designers: HDR photography.
You may have used HDR photography before or at least heard of it, but for the benefit of those not familiar with the process, I'll offer a little primer. HDR stands for High Dynamic Range. The term refers to images that contain large variations of light. For example, a picture of a block of matte black plastic taken on a cloudy day with undirected interior light is Low Dynamic Range; whereas, a picture of sunrise over the grand canyon on a clear day is High Dynamic Range.
Most photographers agree that images with a High Dynamic Range are more interesting subjects. Now we get to a problem. Cameras have a limited range of brightness that their CCDs can handle. Anything above their maximum brightness is burned out to white, and anything below their minimum brightness is pure black. This is bad for both photographers and designers, because any detail that was in an area above or below the range of brightness is lost forever. Enter HDR photography.
HDR photography involves using a tripod to capture multiple images of a subject under different exposures. You aim for a spread such that the longest exposure shows details in the darkest areas, and the shortest shows the details in the brightest areas. There should be no pixel in the scene that is overpowered or underpowered for the entire series. These photos are then processed, and each pixel is assigned a brightness value in floating point, thereby giving an almost limitless dynamic range. The resulting picture looks similar to one taken at a set exposure, except that you can then "choose your exposure", allowing exposures as short or as long as you like. You can even change the exposure on a single portion of the image. Do you see the resemblance to the "plenoptic camera" yet?