Wikipedia does rangefinders

Some edited knowledge from Wiki on the veritable Rangefinder camera

clipped from en.wikipedia.org A rangefinder camera is a camera fitted with a ange-finding focusing mechanism allowing the photographer to measure the subject distance and take photographs that are in sharp focus. Most varieties of rangefinder show two images of the same subject, one of which moves when a calibrated wheel is turned; when the two images coincide and fuse into one, the distance can be read off the wheel. Older, non-coupled rangefinder cameras display the focusing distance and require the photographer to transfer the value to the lens focus ring; cameras without built-in rangefinders could have an external rangefinder fitted into the accessory shoe. The first rangefinders, sometimes called “telemeters”, appeared in the nineteenth century; the first rangefinder camera to be marketed was the 3A Kodak Autographic Special of 1916; the rangefinder was coupled Digital imaging technology was applied to rangefinder cameras for the first time in 2004