Over the years, a myriad of various accessories have been made for the Leica, not just by Leica, but other companies as well. Many of them were made to offer more accurate focusing for the Leica prior to a built-in rangefinder. The accessory FODIS rangefinder was a popular accessory that fit onto the accessory shoe of the camera. Another was the PLOOT, a reflex housing which, when added to the camera, offered accurate focusing for close up and long telephoto work by essentially converting the camera to a single lens reflex.
One such focusing aid was the Flexameter. It too fit onto the accessory shoe of the camera. Unlike a rangefinder, the Flexometer utilized a 50mm Kühn-Rekatar f/2.8 lens which projected an image onto a ground glass where it could be focused. A flip up magnifier allowed for more accurate focusing. The subject distance was then read off the lens and transferred to the camera lens. The Flexameter essentially converted the camera to a twin lens reflex design.
Flexameter on Leica IIIg
Top view with focusing magnifier folded up
Flexameter with original packaging
The Flexameter was made in Wetzlar by the company of Kühn. The name will be familiar to many that are interested in the history of the Leica. Frau Dr. Elsie Kühn-Leitz was the sister of Ernst Leitz II. Her husband Kurt Kühn established a small company in Wetzlar for the manufacture of camera accessories, one of which was the Flexameter in the mid 1930s. Of course cameras other than Leica could be used with the Flexameter also, but it was mostly sold to be used with Leica cameras.
Today the Flexameter is a rather rare collector’s item with only a few left. It is definitely one of the more unique accessories for the Leica cameras. Even though it was made by a company other than Leitz, its uniqueness is further underscored by the connection to the Leitz family and the Leica camera.