Penn State Professor Photographs the Invisible

By Beacon Staff

As photographers, we are always trying to understand the visual world – to make images of what can be seen. So when photography and science collide, the result is quite intriguing.

Gary Settles, a professor of engineering at Pennsylvania State University, uses “shclieren” photography to capture colorful images of scenarios otherwise invisible to the human eye. According to an article in the NY Times (here), Schlieren is German for “streaks” and can refer to “regions of different densities in a gas or a liquid, which can be photographed as shadows using a special technique.”

The process makes it possible to capture the unseen airflow of a burning candle, a hairdryer, a gas leak or the reverberating shock waves of a pistol being fired. And it all started in an attempt to map a cough.

Read the story in the Times (here) and check out a slide show (here).