Photography Hyperfocal
Explain the notion of hyperfocal distance and its practical use in photography?
To work backwards (for simplicity) it is the distance beyond which everything will appear to be in focus.
It has numerous uses, it allows focusing when the object you want in (or out) of focus is surrounded by things that might obstruct easy focusing. It allows you to "pre-focus" say for fast moving wildlife shots.
On older lenses there was always a hyperfocal distance scale on the top of the lens barrel to enable quick and accurate setting. Nowadays they don't bother as most cameras have quite reliable autofocus capability.
Digital Photography 1 on 1: Episode 55: Calculating Hyperfocal Distance