What is a rangefinder?
Rangerfinder cameras are in a league of their own. They are fitted with a range-finding focus that allows the picture taker to judge the distance of focus when taking photographs. Older rangefinders use two images merged together to determine focus whereas modern models allow for the photographer to transmit the focus value to the lens focusing ring. Older models had a separate rangefinder piece and newer models have it attached in the center of the viewfinder to allow for greater range of motion during action shots.