Tessar

The Tessar is one of the most well-known embodiments of photographic lenses and a brand name. It was calculated by Paul Rudolph and patented on April 25, 1902 for the company Carl Zeiss. More than 100 million lenses of this type (original and imitators ) have been built since then.

The Tessar is the type of lens produces a derived from the Cooke triplet Anastigmat. The Tessar is characterized by an unmatched for the development time of field performance. With only small spherical zone errors, best center sharpness and good color correction, it is virtually free of astigmatism and field curvature, the actual optical performance of production or time calculation depends. The low levels of image distortion still satisfies Reproduction claims.

The lens is a into three groups asymmetrically constructed Vierlinser (Greek: tessares = four ). The two lenses of the front group are mounted to each other with an air gap, thereby forming a surface pair with neighboring starch negative sign, while the two lenses of the rear group are cemented together to form a member. This provides a significant performance improvement is achieved compared to the simple triplet. The bezel sits at the Tessar before the hindlimb. It is thus simpler than that already in 1900 presented, also derived from Cooke triplet of Heliar Voigtlander. When Heliar made ​​front and rear element from each of two cemented lenses.

The Tessar initially had only a speed of 1:6.3. Recalculations improved the aperture ratio of 1:4.5 to 1:3.5 or (Ernst Wanders, 1907) and made it in the world as " eagle eye of the camera " known. The Tessar produced from 1.5 to 16.5 cm from 1924 with a light intensity of 1:2.7 and focal lengths did not meet all the expectations, the numbers remained low. A recalculation was the small picture -Tessar 2,8 / 5 cm of Willy Merté from the year 1931. Recalculations also by the light intensity was 2.8 for the medium format Tessar reached 1932 ( focal length 7.5 cm, for example, for Exakta 4x6, 5) or 1933 (8 cm eg for Super Ikonta 6x6).

The first protected logo of Carl Zeiss Jena was derived from the lens diagram of the rear element of the Tessar. This testifies to the importance of this objective for the company Zeiss.

All major lens manufacturers brought Tessar lenses on the market after the rights had expired:

  • Elmar (Leitz )
  • Primotar (also known as " Ihagee Anast. Exaktar " ) ( Meyer -Optik )
  • Minotar, Minoxar, Minar ( Minox 35)
  • Complan ( Minox, miniature camera )
  • Skopar ( Voigtländer )
  • Xenar (Schneider Kreuznach )
  • Ektar (Kodak)
  • Macro Takumar ( Pentax )

Pentacon Exa 1a with Tessar 2,8 / 50

Rollei 35 with Tessar 03/05/40

Minox M.D.C. with lens Minoxar 02/08/35

Minotar lens a Minox 35 GL. You can see the two elements of the panel, directly behind the central locking

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