HDR Plea

HDR stands for High Dynamic Range, and refers to a post-processing method which allows to dramatically increase the dynamic range of a photograph (duh!) by merging different exposures of a same scene. Though the idea is not new, the technique has quickly caught on after new algorithms for the critical tone mapping operation (cramming the increased brightness range into something that a screen or a print can display) were developed a few years ago. HDR is also used a lot in video games as they allow to render a same scene under a variety of lighting conditions, but we will here only discuss the applications to photography.