National Geographic : 1951 Aug
246 A Hummingbird, All Motion Stopped by the Camera, Seems Big and Fierce as a Hawk Hundreds of times brighter than sunlight, a stroboscopic flash lasting 1/5000 of a second reveals intimate details of this Anna's Hummingbird fluttering close to the camera lens (page 250). His wings whir 55 times a second. A hummer flying at top speed is too fast for even the speed flash's brief, brilliant imitation of a lightning bolt. When wings beat 200 times a second, they appear slightly blurred on film. Working with a National Geographic Society grant, the authors in 1950 developed new electronic flash equipment to record habits of several hummingbird species in Arizona. On a similar expedition in 1947, Dr. Edgerton and his associates used a 50-pound flash unit packed in a suitcase. For the later studies, lighter and more convenient equipment was developed in Dr. Edgerton's laboratory at the Massa chusetts Institute of Technology. Ornithologists and scientists took part in the new project. Denver Museum of Natural History was a co-sponsor.