The Australian government is recommending we stay 1.5 meters away from each other, one of several social distancing moves designed to limit spread of the coronavirus.

The US Centers for Disease Control and Prevention advises flu can spread up to 6 feet (1.8 metres). The key message is, the closer you are, the bigger the spray. Similar research is yet to be done ...

It can capture minute details like the fine contours of a fingerprint from as much as one meter (3.3 feet) away, and does not require a long lens.