If you’ve ever seen a rocket engine in action, you probably noticed the bright flame that emerges from the back of it. In fact, that bright fire was probably just an overexposed blob. Nasa’s new High Dynamic Camera system – the HiDyRS-X uses HDR techniques to show that wonderful flame in all its glory. It does so using a special sensor with built in HDR abilities. First here is the high speed movie of the rocket engine:
How it is possible to correctly expose for all the elements of the fire? The answer is in the video description: How is is possible to “record multiple high speed video exposures at once“. If you look at the HiDyRS-X page it has an explanation. Usually HDR is made from several photos with different exposures. An algorithm then picks the right exposure for each pixel: one that is not overexposed or underexposed. This process necessitates several exposures. A killer for high speed photography. But for the HiDyRS-X each pixel on the sensor “knows” to make its own “right” exposure: But it gets even better, using several such cameras and some advanced computational imaging, NASA will be able to generate full 3D HDR movies of rocket engines. Expect bursts of fire coming to a cinema next to you soon.
As an added bonus, youtuber Dmitry Grigorev made a stabilized high speed version of the video where you can see the thrusts vectoring: [via reddit]
