Rangefinder
A rangefinder camera is characterized by having a separate lens and viewfinder that are connected to one another by a rangefinder mechanism. When looking through the viewfinder, two distinct images are displayed, with one of the views being the one that shifts when the focus ring is turned. The image is clear and in focus when the two overlapping images are precisely aligned with one another. Leica cameras in the M line continue to use this lens.
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