The Leica M3 Origin Story
Based on years of de facto teamwork, it could only happen in Wetzlar!
Only a small percentage of great inventions have been conceived and created by a single inspired genius—Nicolaus Otto, who devised and demonstrated the first successful four-stroke internal combustion engine in 1861, John Blankenbaker, who invented the transistor in 1947, and Oskar Barnack, who not only developed and tested the first Leica camera (which went into production as the Leica I, Model A in 1925), but also perfected it by ingeniously integrating a coupled rangefinder and interchangeable lenses into the Leica II (Model D) of 1932 without altering its minimalist form factor one iota! However, a distinct majority of important inventions have been created by actual or de facto collaborations among many individuals or partners, and they often evolved over years or decades—think of the automobile, the airplane, motion pictures, or the modern color TV.
The Leica M3, which commenced production in 1953 and was officially released in 1954, falls into the latter category. Elements of its design date back to the mid ‘30s, many extraordinary engineers and inventors participated in its creation, and their individual efforts were largely guided, coordinated and amalgamated into a supremely functional design by a single individual. What makes the M3 unique is that all these phenomenally talented people were based in one city, Wetzlar, Germany. Indeed, were it not for World War II the landmark Leica M3 may well have debuted in the early to mid 1940s!
Development of the Leica M3: the culmination of 20 years of dedication
Note: I am indebted to the seminal volume, 50 Years Leica M by the late Günther Osterloh as the source for most the information that follows:
Amazingly, the development and design of what would eventually become the Leica M3 was already well under way by the mid-1930s. One key goal was upgrading the horizontal cloth focal-plane shutter from two-dial system with one rotating top dial for fast shutter speeds and a separate non-rotating front dial for setting slow shutter speeds. The new Leica shutter had a single top mounted dial for all shutter speeds, and it didn’t rotate as the shutter fired. The design is detailed in “Reichspatent No. 645856” issued to Ernst Leitz GmbH in Wetzlar in 1934. Enhanced with additional patented refinements by Willi Stein, Dr. Ludwig Leitz, and Friedrich Gath, it provided the basis for the shutter used in the M3. During the war, Leitz was compelled by the government to focus exclusively on military projects, such as aerial cameras, optical instruments, and military Leica cameras and lenses, but some, notably top engineer Willi Stein, managed to sneak in some work on the M3 in their spare time.
In the meantime, Oskar Barnack, who had always been working on improvements to the traditional “Barnack” Leica, transferred these duties to Wilhelm Albert, then head of the photographic design department. When Oskar Barnack passed away on 16 January 1936, the Leica still lacked a combined “universal” range/viewfinder or a coupled exposure meter (which would come much later). However, Barnack did live to see the development of the 1936 prototype Leica IV, which did have a combined range/viewfinder. In the Leica IV was a concave reflecting viewfinder with interchangeable Albada type field frames placed behind the viewfinder, a foreshadowing of the elegant auto-indexing, projected multi-frame viewfinder in the M3. Leitz patents covering this simple solution date back to 31 January 1935 (USA Patent 1,127, 925). Another Leitz German patent (D.R.P. 48425) of 1936 describes a viewfinder with a single system that combines a rangefinder and a telescopic universal viewfinder with sharp image delineation. It also mentions the idea of displaying the respective fields of view with a pre-selector lever or by indexing them automatically as the lens is mounted. Even parallax compensation and field size correction (adjusting the frame line for the reduction in the coverage angle as the lens is focused closer) were referenced in this amazing patent!
Willi Stein, rightfully honored as “the father of the M3” further refined these ideas by devising a more cost-effective system without compromising its performance. Detailed in D.R.P. patent. No 747843 of 1941, the viewfinder employs a flat, semi-transparent mirror with a collimating lens for the frame lines combined with a prism telescope rangefinder. This system avoids crowding the viewfinder with too many frame lines for the various lenses, and Dr. Ludwig Leitz proposed blocking the frames not in use with masks, a concept included in the same patent as an independent claim. The viewfinders of all M Leicas are based on these ideas put forth by Willi Stein and Dr. Ludwig Leitz. The required optical solutions were calculated by Henrich Schneider and Willi Keiner, both of whom had acquired the necessary knowledge in the optical computation department of the Leitz binoculars division. The physical specs of the M range/viewfinder (production engineering) were the responsibility of Robert Eckhardt and Erich Mandler.
The same meticulous care used in designing the range/viewfinder and shutter was also applied in designing the cast body housing and bayonet lens mount of the new Leica M3. The hinged back made for easier film loading without compromising film plane alignment or structural rigidity, and a new film path (channel) and pressure plate improved film flatness. However, the highest priority was designing a new bayonet lens mount that ensured precise parallel seating and exact latching to meet all the requirements for automatic and accurate coupling of lenses, viewfinder, and rangefinder. That formidable task was masterfully accomplished by Hugo Wehrenfennig, who was also responsible for the mechanical design of the new line of M-mount lenses. The four-lobe bayonet mount he developed provides optimum precision and stability while allowing the maximum amount of light coming from the lens to reach the outermost corners of the image. It was also Wehrenfennig’s idea to reduce the flange focal distance of the Leica M to 1mm less than that of the Barnack Leicas, thereby allowing screw-mount (LTM) Leica lenses to mount and focus on M Leicas using simple bayonet adapters. Brilliant!
The new Leica M3 created a worldwide sensation when it was introduced at Photokina 1954 in Cologne, Germany. By 1966, when the last Leica M3 rolled off the bench assembly “production line,” more than 226,000 had been sold, a remarkable achievement for a camera of this quality and complexity. And it was all accomplished by a an exceptional, supremely dedicated group of individuals focused on one overarching objective—creating and constructing the best, most advanced interchangeable lens 35mm rangefinder camera the world had ever seen, and maybe ever will.