Tessar, Planar, Distagon, Biogon, Hologon : was ist das (qu'es aco) ?

[Mistral75]

Carl Zeiss News, le bulletin de la maison Zeiss devenue depuis un blog, a publié une série d'articles sur les noms fameux de l'histoire de Carl Zeiss, leurs origines, les formules optiques et les propriétés des objectifs correspondants.

Le même principe a été adopté à chaque fois : un article introductif dans le bulletin ou sur le blog et, en pièce jointe (pdf téléchargeable), un article de 10-12 pages rédigé par le Dr. Hubert Nasse, Senior Scientist au sein de la Camera Lens Division de Carl Zeiss.

Vous trouverez ci-après les trois premières publications, consacrées respectivement au Tessar (mars 2011), au Planar (juillet 2011) et au trio Distagon - Biogon - Hologon (décembre 2011). Un article sur le Sonnar était prévu mais il n'a pas (encore) été publié.

[Mistral75]

Tessar – History, Legend, Success

Tessar from Carl Zeiss. Anyone interested in photography has at least heard of the name. Photographers around the globe still rave about this lens. What makes it so unique, what special features does it possess and where does the name come from? Dr. Hubert Nasse, Senior Scientist in the Camera Lens Division at Carl Zeiss provides the answers to these and many other questions in a special article.

He takes readers on an exciting journey from the end to the 19th century to the present, where the name Tessar lives on in modern miniature lens in Nokia mobile phones or in the Vario-Tessar for Sony cameras and in the current Tessar T* 4/85 ZM tele lens.

Did you know that the word Tessar is an acronym derived from the Greek word tessares meaning four? It expresses that this lens is comprised of four lens elements. And did you also know that its inventor, Paul Rudolph, calculated the Tessar from its predecessors, the Protar and Unar, although they had completely different designs? According to Dr. Nasse, "It contains elements of both lenses, like a child has genes from both its mother and father."

Readers also learn that the predecessors to the Tessar are based on key glass innovations of the 1880s, as well as how 26-year-old physics professor Ernst Abbe and chemist Otto Schott influenced its development.

L'article complet du Dr Nasse : Tessar - CLN39_en_tessar

[Mistral75]

The Planar lens icon

As Paul Rudolph registered the Planar lens from Carl Zeiss in Jena for patent in 1896, he was clearly unaware that this lens would write photographic history in the following century. Since then, the Planar lens has been installed in countless variations by a large number of manufacturers, with a steady flow of designs using new calculations constantly entering today's market. Up until today, it has served as the foundation for high-performance lenses with impressive color correction, speed, field flattening and distortion correction.

The first Planar lens registered for patent in 1896.

[Mistral75]

Join Dr. Hubert Nasse, Senior Scientist at the Carl Zeiss Camera Lens Division, for a journey of discover of the properties of the Planar lens. His article will tell you how the Planar got its name and why it only enjoyed marginal success during its early years despite its outstanding new properties. Dr. Nasse also gets to the bottom of many technical achievements: for example, what meniscus-shaped, bonded elements are capable of, how the Planar 0,7/50 became world famous or the connection between the S-Planar and Makro-Planar.

L'article complet du Dr Nasse : Planar - en_CLB_40_Nasse_Lens_Names_Planar

[Mistral75]

A fascinating trio: Distagon, Biogon and Hologon

Did you know that the common suffix "gon" in Distagon, Biogon and Hologon means these are all lenses with a large angular view? "Gon" comes from the Greek word "gonia" for "angle."  Like many other manufacturers, Carl Zeiss uses a common end syllable to create consistent naming for its wide-angle lenses.  One of the earliest examples of this approach is the famous "Hypergon" from Goerz which had a 130° angular view. That created lots of excitement at the beginning of the 20th century, as did the later three Zeiss lens types Distagon, Biogon and Hologon.

Clear differences in the build: the Distagon T* 2,8/25 (right) and Biogon T* 4,5/21 (both in a mounting for the Contarex by Zeiss Ikon).

[Mistral75]

In the following article, Dr. Hubert Nasse, Senior Scientist at the Carl Zeiss Camera Lens Division, shares deeper insight into the construction of these three lens types — how they are built and how they function. He also describes their unique strengths and the more technical subtleties. Furthermore, he recounts the most important developments in the history of camera lenses. For example, you'll learn why the image quality of the Biogon made wide-angle lenses so popular in the 1950s, or how the Distagon type established itself as the most important blueprint for building high-performance camera lenses, especially when photographers need a large angular field and a wide aperture.

L'article complet du Dr Nasse : Distagon, Biogon, Hologon - en_CLB41_Nasse_LensNames_Distagon

[Verso92]

Merci pour la présentation, Mistral !
(t'aurais pu traduire...  ;-)

[MBe]

Oui, merci Mistral pour ce partage qui ne pourra qu'améliorer ma très modeste connaissance sur ces optiques.

De plus, malgré le texte en anglais, cela me semble assez compréhensible (en tout cas pour moi!) 

[remico]

Sur un forum il y a des image qui récapitulent différentes formules optiques et les objectifs correspondants, ni toutes les formules optiques ni tous les objectifs mais pas mal d'objectifs Zeiss , Pentax, russes et autres référencés. La liste évolue au cours du fil je mets le lien vers le fil puis les liens vers les dernières versions ainsi qu'un comparatif entre trois 85mm (biotar, ernostar et planar) :

http://forum.mflenses.com/list-of-lens-diagrams-triplets-planars-and-hybrid-lenses-t22934.html

Triplet based lenses (Tessar, Sonnar, etc ...) :

http://img12.abload.de/img/lens_scheme_tri_v5ev1i.png

Planar based lenses :

http://img12.abload.de/img/lens_scheme_dg_v2k8hu.png

Comparatif entre trois 85mm biotar ( Helios 40 85mm f 1.5), ernostar (Asahi auto takumar 85mm f 1,8) et planar (Asahi SMC Takumar 85mm f 1,8) :

http://kogaku.weebly.com/reflex.html

[gargouille]

Merci Mistral je vais y faire un tour.

[dioptre]

Ne pas oublier ce site :
http://dioptrique.info/base/m/m_zeiss.HTM

Sans oublier de cliquer sur la colonne de droite

Qui en plus concerne bien d'autres marques :
http://dioptrique.info/base/m/marques_.HTM
http://dioptrique.info/sommaire/sommaire.HTM