The first 35mm lens

With the advent of 35mm film cameras came the need to design 35mm lenses. The first still cameras designed to use 35mm film inevitably used lenses modified from use on motion-picture cameras, or microscopes. This made sense when the 35mm cine-film used the 18×24mm frame format, however these lenses only covered part of a 24×36mm frame. The figure below shows frame coverage of a cine (movie) lens versus a 35mm lens.

Frame coverage of pre-35mm lenses

For instance the Tourist Multiple used a Bausch & Lomb Zeiss 4-element Tessar (50mm f / 3.5 lens), which was used on motion picture cameras.

Leitz, founded in 1869, began as a company focused on the manufacture of microscopes, and other optical instruments. When work began on the Ur-Leica, Barnack and Berek tried a number of lenses. The simplest option was the 5cm f / 3.5 Zeiss Kino-Tessar movie camera lens. The problem is that the lens could not provide a light spot able to cover the 24×36mm frame format, as it was designed for a 18×24mm format. In addition it produced vignetting not suitable for a camera. The lens they ended up using was the 6-element 42mm f / 4.5 Leitz Mikro-Summar, in a classic double-Gauss formula. This lens had a number of shortcomings, including edge blurring, and a lack of contrast.

The Leitz Mikro-Summar (from 1907 catalog)

The design of a new 35mm lens was the responsibility of German physicist and mathematician, Max Berek (1886-1949). The first 35mm lens developed at Leica was a 50mm f/3.5 Anastigmat. Based on the “Cooke Triplet” lens design, it had 5 elements in 3 groups. The lens was later marginally redesigned, still containing 5 elements in 3 groups, and was given the name Elmax (The name is derived from Ernst Leitz and Max Berak.). These lenses were used on the pre-production Leica-0, of which 31 were manufactured from 1920-1925.

The Anastigmat / Elmax lenses

At that time, the calculation of such a lens was still very complex. Light beam paths from points near or away from the optical axis had to be calculated for three wavelengths and seven refractive surfaces, all by hand using logarithmic tables. Leitz was granted patent No. 343086 for the Anastigmat in 1920.

The first lens formula was difficult to build, so Berek changed the design to a triplet with the last element a cemented doublet, i.e., 4 elements in 3 groups. This lens was renamed Elmar, and was subsequently manufactured for decades (1925-1961). The lens was similar to a Tessar, except for the location of the diaphragm. On the Elmar the diaphragm was located between the first and second elements, rather than the rear two elements.

The Elmar lens

The first lenses which appeared were of the fixed type used on the Leica I. From 1930-1959, the Elmar was made in a screw mount, and an M (bayonet) mount from 1954-1961. From 1930-1932 the lenses were matched with one body, after which they became interchangeable (M39 mount). The lens would evolve to have a maximum aperture of f/2.8, and a minimum aperture of f/22. .

The Leica Elmar 50mm, with screw mount

Specifications: (Original)
50mm f / 3.5 Elmar lens
Angle of view: 45°
No. of elements: 4
Minimum focusing distance: 1.0m
Minimum aperture: 16
Aperture range: 3.5, 4.5, 6.3, 9, 12.5, 16
Weight: 92g

Here are some links to extra info on early Leica lenses:

The origins of 35mm camera film

Full-frame sensors take their dimensions from traditional 35mm film, but where did the ubiquitous 35mm come from?

The second half of the 19th Century spirited the development of many photographic materials and processes. Kodak’s first roll-film camera, the No.1 was introduced in 1888. By 1901, the use of roll-film had become quite common, with Kodak releasing the 120 film format, which was approximately 60mm wide and allowed for various frame sizes. Thomas Edison invented¹ the Kinetoscope in 1893, a device for showing basic film loops, and which used 35mm (1⅜”) gauge cine-film, half the size used in Eastman Kodak cameras. In March 1895, The Lumière Brothers introduced their Cinématographe, the first motion picture film camera, using the same width as Edison, 35mm. By 1909, 35mm had become the standard motion picture film.

Why is it called 35mm film? The 35mm represents the width of the film, irrespective of the size of the frame on the film.

A number of manufacturers started using 35mm cine-film for still photography between 1905 and 1913. The first patent for a 35mm camera was issued to Leo, Audobard and Baradat in England in 1908. It represented one of many patents and prototypes, few of which were produced commercially or even built. The first publicly available 35mm cameras were that used 35mm cine-film were the Tourist Multiple, and the Simplex. The Tourist Multiple, built by US company Herbert & Huesgen, was released in 1913. It was a half-frame camera, taking (750) 18×24mm exposures on 35mm cine-film. The Simplex, invented by Alfred Huger Moses, and was released in 1914. It existed in a number of different models, many of which allowed convertible full/half-frame exposures. The Simplex Model B was the only one to use standard 35mm format (it was only produced from 1914-1918).

The Simplex Model B.

It was Oskar Barnack (1879-1936), who produced the first commercially successful 35mm camera, at the Ernst Leitz Optische Werke in Wetzlar. In 1912, Barnack began work on a new motion picture camera, yet he struggled to get shutter timings right, largely because film emulsions were quite inconsistent. Proper exposure in the early days of motion picture was challenging because of the lack of devices such as photoelectric meters. In response to this, Barnack created a film tester to determine correct exposure settings. Barnack’s device would allow small test exposures to be processed, and exposure issues adjusted accordingly. This prototype device became known as the Ur-Leica, where the prefix “Ur” in German means prime, or original. It was equipped with a Mikro-Summar f / 4.5, 6-element, 42mm lens.

The Leica I (1927) © Kameraprojekt Graz 2015 / Wikimedia Commons

Barnack’s design allowed the camera to move the film horizontally, increasing the frame size to increase to 24×36mm, instead of the 18×24mm exposures of cameras that carried film vertically. This essentially created “double-sized” images. The aspect ratio also changed from 3:4 to 2:3. With the onset of WW1, it was not until 1924 that Leica decided to produce the 35mm camera, with the 35mm Leica I (A) making its first appearance as the Leipzig Spring Fair in 1925. The Leica I had an all-metal housing, a collapsible lens, and a focal-plane shutter. The Leica succeeded because it was compact, and the quality of the exposures was as good as the more commonly used roll film.

So why did 35mm film become so successful? It was partially to do with cost. Due to its use in the cinematic industry, 35mm motion picture film was widely available, and inexpensive. The number of exposures which could be loaded into a camera was 40. Initially the film had to be loaded in the dark, however Barnack soon realized this was a problem and developed a reloadable cassette which could easily be inserted into the camera, and could accommodate 36 exposures. By 1932, Leica’s competitor Zeiss had introduced the 35mm Contax, and Kodak entered the market in 1934 with the Retina I.

¹ It is widely believed that the Kinetoscope was actually designed by one of Eastman’s employees, William Dickson.

For more information on early 35mm cameras check out Max Bertacchi’s page dedicated to early 35mm cameras, or early Leica’s.