Rocket launches create a fiery spectacle, but they also create problems for Nasa engineers who want to see exactly what happens when the engines ignite. A complete view of a rocket exhaust provides details of thermal and physical dynamics that can be used to create high-fidelity computer models. The fury of blastoff, however, shrouds the scene in exceedingly bright flames and obscuring smoke.

Now, with a clever six-camera setup called Walle, Nasa has found a way to see into a rocket plume or any other brilliant blast. The system merges the clearest pixels of images taken by six cameras; the combined shots offer a superhuman view of the trickiest high-contrast scenes. Walle’s creators at Nasa’s Ames Research Centre built it from spare high-speed cameras. When Walle starts recording video, one camera properly exposes the dimmest parts of a scene, leaving the brighter parts blown-out white. The next camera uses a filter to capture brighter parts of the image the other camera couldn’t. The remaining cameras use a series of increasingly dark filters until all bright and dark sections are properly exposed. Software then strips out the jet-black and pure-white pixels in each of the six sets and fuses the correctly exposed portions into one shot.

But Walle is capable of much more than stunning visuals. It might also record high-contrast explosions to capture images of chunks of shrapnel inside the blast that are too dim for regular cameras to see. Another potential use: to record the exposure of materials to searing-hot plasma inside an arc jet, a device used to simulate the heat of atmospheric re-entry.

Watch a side-by-side comparison video showing a one-camera view of the STS-134 launch (left) with the six-camera composite view (right)...

Imaging experts funded by the Space Shuttle Program and located at Nasa's Ames Research Centre prepared the composite view by merging nearly 20 000 photographs taken by a set of six cameras capturing 250 images per second at the STS-134 launch on 16 May 2011.