Data sheet: Carl Zeiss Jena Prakticar 135 mm f/3.5

Pekka Buttler, 11/2022

Specifications

The table below summarizes the lens’ key specifications (measurements are based on the pictured sample):

Brand:Carl Zeiss JenaLens namePrakticar 3.5/135 MC
Focal length(s)1135 mmAngle-of-view218 °
Maximum Aperturef/3.5In Production1978–1990
Lens mountsPraktica BSubfamily (if applicable)––
Length380,3 mmDiameter462,4 mm
Filter ring diameter49 mmWeight384 grams
Lens element count4Lens group count3
Aperture blades (S/R/C)56 RFocus throw330 °
Minimum focusing distance1 msMaximum magnification1:5,2
Has manual aperture ringYESHas Manual focus ringYES

Further notes:
• Prakticar is the name given to all Carl Zeiss Jena and Pentacon (and many other) lenses designed for the Praktica B mount. Hence, while the lens’ name ring says Prakticar, the lens is a member of the family of Sonnar (design) lenses.
• Alike all Praktica B mount lenses, this lens has three electronic contacts that it uses to communicate selected aperture to the camera body and a physical aperture stop-down lever.
• The 135 mm f/3.5 Prakticar was manufactured in only one variant, and is considerably less common than its M42 ancestor/sibling.
• The lens offers a built-in, extendable hood.

History of Carl Zeiss Jena

There are few names in camera optics more illustrious than that of Carl Zeiss. The company was founded in the German town of Jena in 1846 by Carl Zeiß (hence: ‘Carl Zeiss Jena‘). During 1846–1945 there are few major developments in lens optics that the company was not involved in. Names that are even today well-known in optics – such as Planar (1896), Tessar (1902), Sonnar (1929), and Biotar (1939) (as well as many names that only optics-buffs know) – were the product of Zeiss’ first century of technological innovation.

After the Second World War Germany was divided into a Soviet zone (subsequently: East Germany) and the west-allied zones (subsequently: West Germany). While the Zeiss works resided in Jena (optics and glasses) and Dresden (cameras), which were in the Soviet sector, a contingent of Zeiss managers decided to move west and ended up setiting up shop in the small town of Oberkochen in the American sector under the name of Opton Optische Werke Oberkochen GmbH. As the relations between the former allied deteriorated and the split into East and West Germany became all the more real, the Oberkochen works changed their name first to Zeiss-Opton and later to Carl Zeiss.

What ensued was a lengthy international trademark dispute with both Zeiss’ (Jena and Oberkochen) laying claim to the name ‘Carl Zeiss’. The resulting stalemate – emblematic of the Cold War in its entirety – resulted in that Carl Zeiss Opton was allowed to use the name Carl Zeiss in the West, but had to use the Opton brand in the East bloc, whereas Carl Zeiss Jena was the only real Carl Zeiss as far as the east bloc was concerned, but could – mostly – not use the Carl Zeiss -name for exports to the West6. The fact remains however, that – starting in 1946 from a shared base – Jena and Oberkochen developed as two independent companies for more than 40 years. After German reunification also Zeiss East and Zeiss West were united again, and have since again been at the undoubtable forefront of lens development.

This lens harkens to the time of the cold-war and the East/West split. During the entire Cold War period, VEB Carl Zeiss Jena was seen by the country’s leadership both as a paragon of the East German technology industry and a showcase of the socialist/communist system as well as a major source of exports (and hence, western currencies). Within the centrally directed economy’s hierarchy, Carl Zeiss Jena therefore had a more prestigious role than other East German optics manufacturers (prominently Meyer-Optik Görlitz and, later, Pentacon), meaning that Carl Zeiss Jena received privileged access to tools and materiel (including the first computer in East Germany) and that its products were always considered the premium alternative.

History of the Sonnar design

The Sonnar design (together with the Planar and Tessar designs) is among the most illustrious optical lens designs ever to have come out of Carl Zeiss’ design bureau. Originally conceived in 1929 by Ludwig Bertele, the entire evolution of the Sonnar was by no means the result of a solo design effort.

While ‘Sonnar’ was traditionally a trademark belonging to another photographic manufacturer, that company had been merged with Zeiss, allowing the adoption of the Sonnar name for this design, which was characterized by (for its time) exceptionally wide apertures (Sonne is german for Sun ==> Bright as the sun). While initially offered as a 50 mm f/2 design for rangefinder cameras, this was quickly superseded by an even brighter 50 mm f/1.5 design.

While originally intended as a fast standard lens for rangefinder cameras (predominantly in LTM and Contax/Kiev mounts), the Sonnar design was unusable for standard lenses on SLR mounts due to the long back focus distance inherent to SLR designs (that need to make space for the mirror box). Hence, on SLRs Sonnars became one of the dominant approaches for making large-aperture short tele and tele lenses (85–200 mm). However, because the basic Sonnar design demands a great deal of glass (huge chunks of large-diameter glass) at the front-end of large aperture Tele lenses, such designs invariably result in not only heavy lenses, but also in distinctly front-heavy lenses.

The basic approach behind the Sonnar is to produce a lens that has as high element-to-group ratio (e.g. a 7 element, 3 group lens) in order to minimise the number of air-glass interfaces, to thereby decrease flaring and increase transmission. Very often these designs were based on using triplets wherein the central lens of the triplet would be made of a type of glass that aimed to emulate an air lens.

Interestingly, while early (1930s-1940s) Sonnars were all characterized by a 3-group 6–7-element design, advancements in both calculation methods and optics contributed to that later (intermediate) Sonnar-type designs (both by Zeiss and others) typically used fewer lens elements (a typical short tele Sonnar would be a 5 elements in 3 groups). Further, as coating technology developed and minimising the number of air-glass interfaces stopped being an absolute priority, many manufacturers started introducing real air lenses to split up the Sonnar-typical triplets. However, from a strict design-perspective, whether such designs still are worthy of being referred to as Sonnars is debatable.

In either way, the Sonnar name has immense marketing value, which is why you will find the Sonnar-moniker in many lenses that share very little (if anything) with the original design (one such example here).

Versions Genealogy of the 135/3.5 Prakticar

While the 135 mm f/3.5 Prakticar was produced in only one variant, that lens is so closely related to other CZJ 135 mm Sonnars, that the entire lineage will be presented below (in reverse chronological order):

• The Praktica B (Prakticar) version (1978–1990, pictured above) was offered in the Praktica Bayonet mount, and is optically and mechanically identical to the later M42 variant, while (designwise) being in line with the Praktica B look.
• The late M42 version (1975–1990) was offered in both M42 (auto) and M42 (electric) variants. The aperture mechanics were redesigned in 1976/77 leading to two sub-types of both variants. Both sub-types were multicoated, and cosmetically both sub-types were of the all-black design. For imagery comparing the late version’s first and second subtypes, I have to refer you otherwhere.
• The early M42 version (1965–1975) was offered only in M42 auto mount and (cosmetically) followed the zebra pattern. This lens is coated, but lacks multicoating.
• The predecessor of the Early M42 version was the Carl Zeiss Jena Sonnar 135 mm f/4, that was available in Exakta mount and M42 (preset and auto) mount versions. This lens itself is very closely related to various 135/4 Sonnar designs for rangefinders.

Adapting

This lens cannot be used natively on any current SLR or dSLRs. To use it in its native environment, you will need a Praktica B mount film body. Luckily there are a lot of those available, and many of them are still in perfect working order.

Thanks to being a fully manual lens (manual aperture, manual focus), the lens can be adapted to all mirrorless cameras using a suitable adapter. Moreover, Praktica B lenses are so uncomplicated that a simple ‘dumb adapter’ will do the job perfectly (The electronic contacts communicate only from the lens to the camera and do not impinge on adapting). However, due to that the Praktica B mount never was so successful, one should not expect special adapters (helicoid adapters, tilt/shift adapters) to be easily available. Alternatively, one can choose to daisy-chain adapters (e.g. Praktica B->Canon EF; Canon EF –> mirrorless) which not only opens up possibilities for special adapters, but also allows using speed boosters for those photographers that use smaller than full-frame sensors.

Using Praktica B lenses on dSLRs can also be an easy option, depending on which dSLR.
• Canon EF has the shortest flange focal distance among full-frame dSLR’s and Canon’s wide range of dSLRs are able to mount Praktica B lenses perfectly using a suitable adapter ring.
• With other dSLR mounts (Minolta/Sony A; Pentax K; Nikon F) the relationship between flange focal differences becomes an issue, leading to that adapting will necessitate an adapter that uses corrective optics to allow reaching infinity focus.

Footnotes

1 Focal length is (unless stated otherwise) given in absolute terms, and not in Full-frame equivalent. For an understanding of whether the lens is wide/tele, see ‘Angle-of-view’.

2 Picture angle is given in degrees (based on manufacturers’ specs) and concerns the diagonal picture angle. Rule of thumb:
> 90 ° ==> Ultra-wide-angle
70–90 ° ==> Wide-angle
50–70 ° ==> Moderate wide-angle
40–50 ° ==> ‘Standard’ or ‘normal’ lens
20–40 ° ==> Short tele lens
10-20 ° ==> Tele lens
5-10 ° ==> Long tele lens
< 5 ° ==> Ultra-tele lens

3 Length is given from the mount flange to the front of lens at infinity.

4 Diameter excludes protrusions such as rabbit ears or stop-down levers.

5 S=straight; R=rounded; C=(almost)circular at all apertures.

6 Online one can find many lengthy and heated disputes stating that only Jena/Oberkochen is the true Carl Zeiss. While many of these discussions are riddled with misconceptions and a poor grasp of facts and timings, they largely also tend to be tainted by ideologies. Those discussions that focus on claims of one or the other Zeiss not really having rights to using designs developed at pre-war Zeiss are especially ludicrous because after the war practically the entire patent catalogue of pre-war German patents was given freely to everyone (the allied saw this as a form of reparations), hence also kickstarting the Japanese optics industry’s ascendancy (the Japanese optics companies were the most avid users of German optics patents).