Qualitative Real-Time Schlieren and Shadowgraph Imaging of Human Exhaled Airflows: An Aid to Aerosol Infection Control
Figure 3
Typical position of a single subject in front of the schlieren mirror.
The exhalation puffs can be seen as disturbances in the ‘texture’ in front of the head (images obtained using a Nikon D7000 SLR in HD 1920×1080 live video mode).