Ludwig Bertele
Encyclopedia
Ludwig Jakob Bertele was a German optics
constructor. His developments received universal recognition and serve as a basis for considerable part of optical designs, which are used in modern world.
, to an architect’s family.
In 1916 he began to work as an assistant of optics designer in Rodenstock
firm in Munich. In 1919 he went to Dresden
to work in Ernemann Company (Krupp-Ernemann Kinoapparate AG). He worked there under the supervision of professor doctor August Klughardt as designer of optics.
In 1919 Ludwig Bertele started to develop a type of optical scheme, subsequently known as Ernostar. He has taken for a basis an optical scheme of cinema lens Ultrastigmat, a modified triplet
, which was calculated by Charles C. Minor in 1916 and being produced by Gundlach Company. The main purpose was the increasing of light-gathering power and diminution of aberration
.
In 1923, after four years of intensive efforts, he has patented his first ultra high-aperture objective Ernostar F/2, its successive versions followed till 1926. That lens was fitted to the Ermanox camera, which was specially developed for photo reportage. This was the first camera having sufficient speed and image quality for candid photography
in available light conditions. The pictures of prominent political figures taken with it by Erich Salomon
are widely
known.
After the foundation of Zeiss Ikon in 1926, as a result of integration of companies ICA (Internationale Camera Actiengesellschaft), Optische Anstalt CP Goerz
, Contessa-Nettel and Ernemann-Werke with Carl Zeiss
, L. Bertele continued his work in Dresden
except for a short trip to USA in 1929. Experimental optical workshop was given at the disposal of Bertele. That shop made all examples and prototypes of Bertele’s calculations. Every lens got a unique five-cipher number; often a current number of the variant was also engraved.
In last 1920s Bertele began the development of a series of excellent lenses, based generally on the second Ernostar type, which was developed in 1924 (i.e., each lens had a single positive element in front of it followed by a thick negative meniscus-shaped component, with a positive element behind). In 1931 the first example of such lenses appeared. It received the name Sonnar
.
That glass – objective consisted of seven elements in three groups with maximum aperture
F/2. Main difference from his predecessor Ernostar was lesser number of optical groups and, therefore, lesser light dispersion and bigger contrast
. Those lenses proved extraordinarily successful and got high marks from specialists.
In 1932 Sonnar F/1.5 appeared which was fitted to Zeiss Ikon’s 35mm Contax
cameras. Following versions of Sonnar with focal length
s from 50 till 300mm having been developed till 1940.
Around 1934 Bertele, having taken scheme of Sonnar as a basis, created first wide-angle lens Biogon
with 60° viewing angle.
In 1935 Ludwig Bertele calculated the Sonnar 180/2.8 on the occasion of the XI summer Olympic Games
of 1936 in Berlin
- fabulous lens, which made an image of highest quality with beautiful bokeh
. This objective has been appreciated by photographers and collectors up to now.
From 1943 till 1945 Ludwig Bertele was working in Steinheil
firm, situated in Munich
. That firm worked for Imperial Ministry of aviation.
In 1946 he moved to Switzerland
, where he founded optical bureau and started to work in Wild Heerbrugg Company (now Leica Geosystems
) in the field of photogrammetry
and geodesic devices. In 1950 he created aerial 90° viewing-angle lens Aviogon, which was free from optical aberrations. Distortion
was less than 10 microns at any point of the image field, and the resolution
at F/4.5 was excellent. The new lens quickly replaced the Topogon and Metrogon as the standard lens for aerial photography and photogrammetry. This objective, as well as 120° Super Aviogon, which appeared in 1956, won a great number of prizes and merited general recognition.
At the same time he computed new optical designs for Carl Zeiss in Oberkochen
. Thus, Biogon with 90° viewing-angle appeared in 1951. This new design was the basis of ultra wide-angle lenses, such as Biogon F/4.5 21 mm 1951 for Contax
; Biogon F/4.5 38 mm 1954 for Hasselblad
; Biogon F/4.5 53 mm and Biogon F/4.5 75 mm 1955 for Linhof
. In addition to this he developed objectives for Schacht firm and got special tasks for computations of ocular
s etc.
He left the firm in 1956, continuing his own research and giving consultations. In 1959 he was awarded rank of honorable Doctor of Philosophy
of Zurich University
and he appraised it greatly.
Having retired in 1973, Ludwig Bertele continued to work a lot. He received his last patent
in 1976.
Last years he lived in a small town Wildhaus
in canton St. Gallen
in Switzerland
.
He died on 16 November 1985.
Optics
Optics is the branch of physics which involves the behavior and properties of light, including its interactions with matter and the construction of instruments that use or detect it. Optics usually describes the behavior of visible, ultraviolet, and infrared light...
constructor. His developments received universal recognition and serve as a basis for considerable part of optical designs, which are used in modern world.
Biography
Ludwig Jakob Bertele was born 25 December 1900 in MunichMunich
Munich The city's motto is "" . Before 2006, it was "Weltstadt mit Herz" . Its native name, , is derived from the Old High German Munichen, meaning "by the monks' place". The city's name derives from the monks of the Benedictine order who founded the city; hence the monk depicted on the city's coat...
, to an architect’s family.
In 1916 he began to work as an assistant of optics designer in Rodenstock
Rodenstock GmbH
The Rodenstock GmbH is a renowned German manufacturer headquartered in Munich and the only brand producer of the entire spectacles product worldwide...
firm in Munich. In 1919 he went to Dresden
Dresden
Dresden is the capital city of the Free State of Saxony in Germany. It is situated in a valley on the River Elbe, near the Czech border. The Dresden conurbation is part of the Saxon Triangle metropolitan area....
to work in Ernemann Company (Krupp-Ernemann Kinoapparate AG). He worked there under the supervision of professor doctor August Klughardt as designer of optics.
In 1919 Ludwig Bertele started to develop a type of optical scheme, subsequently known as Ernostar. He has taken for a basis an optical scheme of cinema lens Ultrastigmat, a modified triplet
Cooke triplet
The Cooke triplet is a photographic lens designed and patented in 1893 by Dennis Taylor who was employed as chief engineer by T. Cooke & Sons of York...
, which was calculated by Charles C. Minor in 1916 and being produced by Gundlach Company. The main purpose was the increasing of light-gathering power and diminution of aberration
Aberration
An aberration is something that deviates from the normal way.Aberration may refer to:In optics and physics:*Optical aberration, an imperfection in image formation by an optical system...
.
In 1923, after four years of intensive efforts, he has patented his first ultra high-aperture objective Ernostar F/2, its successive versions followed till 1926. That lens was fitted to the Ermanox camera, which was specially developed for photo reportage. This was the first camera having sufficient speed and image quality for candid photography
Photography
Photography is the art, science and practice of creating durable images by recording light or other electromagnetic radiation, either electronically by means of an image sensor or chemically by means of a light-sensitive material such as photographic film...
in available light conditions. The pictures of prominent political figures taken with it by Erich Salomon
Erich Salomon
Erich Salomon was a German-born news photographer known for his pictures in the diplomatic and legal professions and the innovative methods he used to acquire them....
are widely
known.
After the foundation of Zeiss Ikon in 1926, as a result of integration of companies ICA (Internationale Camera Actiengesellschaft), Optische Anstalt CP Goerz
Goerz (company)
C. P. Goerz was founded in 1886 by Carl Paul Goerz. Originally, it made geometrical drawing instruments for schools. From 1888 it made cameras and lenses. During the First World War, Goerz's main production was for the German and Austrian military. Goerz is known primarily for Anschuetz...
, Contessa-Nettel and Ernemann-Werke with Carl Zeiss
Carl Zeiss
Carl Zeiss was a German maker of optical instruments commonly known for the company he founded, Carl Zeiss Jena . Zeiss made contributions to lens manufacturing that have aided the modern production of lenses...
, L. Bertele continued his work in Dresden
Dresden
Dresden is the capital city of the Free State of Saxony in Germany. It is situated in a valley on the River Elbe, near the Czech border. The Dresden conurbation is part of the Saxon Triangle metropolitan area....
except for a short trip to USA in 1929. Experimental optical workshop was given at the disposal of Bertele. That shop made all examples and prototypes of Bertele’s calculations. Every lens got a unique five-cipher number; often a current number of the variant was also engraved.
In last 1920s Bertele began the development of a series of excellent lenses, based generally on the second Ernostar type, which was developed in 1924 (i.e., each lens had a single positive element in front of it followed by a thick negative meniscus-shaped component, with a positive element behind). In 1931 the first example of such lenses appeared. It received the name Sonnar
Zeiss Sonnar
The Sonnar is a photographic lens originally designed by Dr. Ludwig Bertele in 1924 and patented by Zeiss Ikon. It was notable for its relatively light weight, simple design and fast aperture. The name "Sonnar" is derived from the German word "Sonne", meaning sun...
.
That glass – objective consisted of seven elements in three groups with maximum aperture
Aperture
In optics, an aperture is a hole or an opening through which light travels. More specifically, the aperture of an optical system is the opening that determines the cone angle of a bundle of rays that come to a focus in the image plane. The aperture determines how collimated the admitted rays are,...
F/2. Main difference from his predecessor Ernostar was lesser number of optical groups and, therefore, lesser light dispersion and bigger contrast
Contrast
Contrast may refer to:* Contrast , the difference in color and light between parts of an image* Contrast , expressing distinctions between words...
. Those lenses proved extraordinarily successful and got high marks from specialists.
In 1932 Sonnar F/1.5 appeared which was fitted to Zeiss Ikon’s 35mm Contax
Contax
Contax was a camera brand noted for its unique technical innovation and a wide range of Zeiss lenses, noted for their high optical quality. Its final incarnation was a line of 35 mm, medium format and digital cameras engineered and manufactured by Kyocera, and featuring modern Zeiss optics...
cameras. Following versions of Sonnar with focal length
Focal length
The focal length of an optical system is a measure of how strongly the system converges or diverges light. For an optical system in air, it is the distance over which initially collimated rays are brought to a focus...
s from 50 till 300mm having been developed till 1940.
Around 1934 Bertele, having taken scheme of Sonnar as a basis, created first wide-angle lens Biogon
Biogon
Biogon is a brand name of Carl Zeiss for a series of photographic camera lenses. Biogons are typically wide angle lenses.The first Biogon was created in 1935 by Ludwig Bertele, then referenced by designer Zeiss Ikon Dresden, the Contax created as a modification of the then Sonnar...
with 60° viewing angle.
In 1935 Ludwig Bertele calculated the Sonnar 180/2.8 on the occasion of the XI summer Olympic Games
1936 Summer Olympics
The 1936 Summer Olympics, officially known as the Games of the XI Olympiad, was an international multi-sport event which was held in 1936 in Berlin, Germany. Berlin won the bid to host the Games over Barcelona, Spain on April 26, 1931, at the 29th IOC Session in Barcelona...
of 1936 in Berlin
Berlin
Berlin is the capital city of Germany and is one of the 16 states of Germany. With a population of 3.45 million people, Berlin is Germany's largest city. It is the second most populous city proper and the seventh most populous urban area in the European Union...
- fabulous lens, which made an image of highest quality with beautiful bokeh
Bokeh
In photography, bokeh is the blur, or the aesthetic quality of the blur, in out-of-focus areas of an image, or "the way the lens renders out-of-focus points of light."...
. This objective has been appreciated by photographers and collectors up to now.
From 1943 till 1945 Ludwig Bertele was working in Steinheil
Steinheil
Steinheil is a surname and may refer to:* Heinrich Steinhowel , a Swabian author, humanist, and translator...
firm, situated in Munich
Munich
Munich The city's motto is "" . Before 2006, it was "Weltstadt mit Herz" . Its native name, , is derived from the Old High German Munichen, meaning "by the monks' place". The city's name derives from the monks of the Benedictine order who founded the city; hence the monk depicted on the city's coat...
. That firm worked for Imperial Ministry of aviation.
In 1946 he moved to Switzerland
Switzerland
Switzerland name of one of the Swiss cantons. ; ; ; or ), in its full name the Swiss Confederation , is a federal republic consisting of 26 cantons, with Bern as the seat of the federal authorities. The country is situated in Western Europe,Or Central Europe depending on the definition....
, where he founded optical bureau and started to work in Wild Heerbrugg Company (now Leica Geosystems
Leica Geosystems
Leica Geosystems based in eastern Switzerland produces products and systems for surveying and geographical measurement...
) in the field of photogrammetry
Photogrammetry
Photogrammetry is the practice of determining the geometric properties of objects from photographic images. Photogrammetry is as old as modern photography and can be dated to the mid-nineteenth century....
and geodesic devices. In 1950 he created aerial 90° viewing-angle lens Aviogon, which was free from optical aberrations. Distortion
Distortion
A distortion is the alteration of the original shape of an object, image, sound, waveform or other form of information or representation. Distortion is usually unwanted, and often many methods are employed to minimize it in practice...
was less than 10 microns at any point of the image field, and the resolution
Optical resolution
Optical resolution describes the ability of an imaging system to resolve detail in the object that is being imaged.An imaging system may have many individual components including a lens and recording and display components...
at F/4.5 was excellent. The new lens quickly replaced the Topogon and Metrogon as the standard lens for aerial photography and photogrammetry. This objective, as well as 120° Super Aviogon, which appeared in 1956, won a great number of prizes and merited general recognition.
At the same time he computed new optical designs for Carl Zeiss in Oberkochen
Oberkochen
Oberkochen is a town in the Ostalbkreis, in Baden-Württemberg, Germany.-Economy:After WWII the allied troops moved parts of the Carl Zeiss Company in Jena to Oberkochen. Today the headquarter of the Carl Zeiss AG is located in Oberkochen...
. Thus, Biogon with 90° viewing-angle appeared in 1951. This new design was the basis of ultra wide-angle lenses, such as Biogon F/4.5 21 mm 1951 for Contax
Contax
Contax was a camera brand noted for its unique technical innovation and a wide range of Zeiss lenses, noted for their high optical quality. Its final incarnation was a line of 35 mm, medium format and digital cameras engineered and manufactured by Kyocera, and featuring modern Zeiss optics...
; Biogon F/4.5 38 mm 1954 for Hasselblad
Hasselblad
Victor Hasselblad AB is a Swedish manufacturer of medium-format cameras and photographic equipment based in Gothenburg, Sweden.The company is best known for the medium-format cameras it has produced since World War II....
; Biogon F/4.5 53 mm and Biogon F/4.5 75 mm 1955 for Linhof
Linhof
Linhof is a German company, founded in Munich in 1887 by Valentin Linhof. The company is well known for making premium rollfilm and large format film cameras...
. In addition to this he developed objectives for Schacht firm and got special tasks for computations of ocular
Ocular
Ocular may refer to:* Eye, an organ of vision that detects light* Eyepiece, the optical element closest to the eye in a telescope or microscope* Ocular scale, a type of scales in reptilesRomania:...
s etc.
He left the firm in 1956, continuing his own research and giving consultations. In 1959 he was awarded rank of honorable Doctor of Philosophy
Doctor of Philosophy
Doctor of Philosophy, abbreviated as Ph.D., PhD, D.Phil., or DPhil , in English-speaking countries, is a postgraduate academic degree awarded by universities...
of Zurich University
University of Zurich
The University of Zurich , located in the city of Zurich, is the largest university in Switzerland, with over 25,000 students. It was founded in 1833 from the existing colleges of theology, law, medicine and a new faculty of philosophy....
and he appraised it greatly.
Having retired in 1973, Ludwig Bertele continued to work a lot. He received his last patent
Patent
A patent is a form of intellectual property. It consists of a set of exclusive rights granted by a sovereign state to an inventor or their assignee for a limited period of time in exchange for the public disclosure of an invention....
in 1976.
Last years he lived in a small town Wildhaus
Wildhaus
Wildhaus is a village in the new municipality of Wildhaus-Alt St. Johann in the Wahlkreis of Toggenburg in the canton of St. Gallen in Switzerland. The municipalities of Alt St. Johann and Wildhaus merged into the municipality of Wildhaus-Alt St. Johann on 1 January 2010.The reformer Huldrych...
in canton St. Gallen
Canton of St. Gallen
The Canton of St. Gallen is a canton of Switzerland. St. Gallen is located in the north east of Switzerland. It covers an area of 2,026 km², and has a population of . , the population included 97,461 foreigners, or about 20.9% of the total population. The capital is St. Gallen. Spelling...
in Switzerland
Switzerland
Switzerland name of one of the Swiss cantons. ; ; ; or ), in its full name the Swiss Confederation , is a federal republic consisting of 26 cantons, with Bern as the seat of the federal authorities. The country is situated in Western Europe,Or Central Europe depending on the definition....
.
He died on 16 November 1985.
Interesting facts
- Name Sonnar was derived from German word “Sonne” (Sun).
- It is interesting to note that the name Sonnar had been used previously by the Contessa Company for one of their folding cameras and for the Tessar-typeTessarThe Tessar is a famous photographic lens design conceived by physicist Paul Rudolph in 1902 while he worked at the Zeiss optical company and patented by Zeiss; the lens type is usually known as the Zeiss Tessar....
lens fitted to it. After Contessa became part of Zeiss Ikon the name Sonnar became Zeiss’s property.
- Optical scheme Ernostar, developed by Ludwig Bertele, serves as a basis for lens Canon EF 135mm F/2.0 L, which is very popular among portrait photographers. And Sonnar scheme is used in an amazing objective Carl Zeiss Sonnar 135/1.8 T* ZA, which is being produced for SonySony, commonly referred to as Sony, is a Japanese multinational conglomerate corporation headquartered in Minato, Tokyo, Japan and the world's fifth largest media conglomerate measured by revenues....
SLR cameras.