schlieren: shadows, smokes and mirrors
Updated: Oct 7, 2017
Schlieren photography is a technique of capturing minute changes in the refractive index of the air - which appear as shadows - using a clever combination of light and mirrors. This technique can be used to visualize air-flow, which induces local changes in density and refractive index. Below are some of the Schlieren videography that I performed with a student.
Striking a match ...
A droplet bouncing off a lotus-effect surface. Air vortices created upon impact are clearly visible.
Learn more about Schlieren photography here and here. The information from the links should allow you to make a similar set-up at home (or in the lab). You will need a point light source, a parabolic mirror, and of course a camera. We purchased a parabolic mirror from Thorlab, but it is probably cheaper to get it from an astronomy specialty shop.