Among many digital camera firsts, the R-D1 is the world's first rangefinder digital camera. A rangefinder is a type of camera that has a built-in device for measuring distance based on the principles of triangulation. The photographer focuses the camera by superimposing two slightly different views of a scene with the rangefinder. In general, compared to an auto-focus system, performance does not change even if lenses are swapped, and focus can be achieved quickly, accurately and with a light level that is nearly the same as the unaided eye, even in dimly lit locations. In addition, since the field of view is not blocked by the action of a shutter as it is with a single-lens reflex camera, the photographer will not miss the decisive moment.
The R-D1 is also the world's first digital camera to accept Leica L- and M-mounts. As such, it offers a platform that links the future with the past. A huge number of lens types - more than 200 - have been created and sold over the long history of photography. This camera gives twenty-first century photographers a way to use these famed lenses from a strong photographic heritage. The camera gives photographers the chance to develop a new cult of photography by allowing them to resurrect their familiar old lenses in a digital world. The R-D1 also uses the world's first 1x viewfinder, enabling photographers to view scenes - including panoramas - through the camera as if they were looking at scenes using their naked eyes. The camera also has the advantage of improved focus precision compared to low magnification optical finders.