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The Leica II is a Barnackrangefinder camera introduced by Leica in 1932. They were the first Leica cameras with a built-in rangefinder. Several models were produced over the years, in parallel with the Leica III series from 1933.
The Leica II uses a coupled rangefinder distinct from the viewfinder. The viewfinder is set for a 50 mm lens; use of shorter or longer lenses requires installing an alternate viewfinder on the accessory socket.
A mere four copies of the gold-plated Leica Luxus II were made. In 2013, one sold at auction in Hong Kong for $HK4 million, after featuring on the BBC's Antiques Roadshow programme. The whereabouts of the other three models are not recorded.
The popular Soviet camera, the FED 1, was a clone of the Leica II.
Unification of the rangefinder and the viewfinder occurred with the introduction of the Leica M3, allowing quick framing and focusing in a single operation. The M3 viewfinder is also able to display viewlines for 50, 90 and 135 mm lenses