The Leica III is a Barnack model rangefinder camera introduced by Leica in 1933, and produced in parallel with the Leica II series.

Several models were produced over the years, with significant improvements.

The Leica III uses a coupled rangefinder distinct from the viewfinder.

The viewfinder is set for a 50mm lens; use of shorter or longer lenses requires installing an alternate viewfinder on the accessory socket.

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