Pekka Buttler, 11/2022
The table below summarizes the lens’ key specifications (measurements based on pictured sample):
|Subfamily (if applicable)
|Filter ring diameter
|Lens element count
|Lens group count
|Aperture blades (S/R/C)5
|Minimum focusing distance
|Has manual aperture ring
|Has Manual focus ring
• The Trioplan is famous for its Soap Bubble bokeh. Soap Bubble Bokeh is an extreme case of overcorrected spherical aberration. Read some of the theory here.
• This Trioplan-N lens has the pass-through stop-down mechanism typical to late-era Exakta mount lenses (you press the lever/pod at the base of the lens, which stops down the aperture prior to actuating the camera’s shutter release). But it also offers a manual/automatic aperture control ring (in front of the focus ring). If you use the lens adapted, you will likely want to put the Trioplan-N in manual mode.
• Today the Trioplan is today an immensely sought-after lens, and is one of the ‘Crown Jewels’ of the new Meyer-Optik Görlitz (a new company that produces remakes of some MOG classics).
• There is considerable irony in that, because (the real) Meyer-Optik Görlitz used to (until the late 60s) sell the Trioplan as a simple and cheap portrait lens (the Trioplan was among the cheapest lenses available).
• The introduction of the Meyer-Optik Orestor 100/2.8 [data sheet] marked the end of the Trioplan.
• There are two major versions of the 100 mm Trioplan. See more in versions.
• For further notes on Meyer-Optik Görlitz and especially their naming logic, see the JAPB article on MOGnames (the company’s later history is summarised below).
History of Meyer-Optik Görlitz
The original Meyer-Optik Görlitz (not the modern company that has taken the classic company’s name) was founded in the town of Görlitz (modern-day Germany) by Hugo Meyer in 1896, and remained in existence until the state-directed merger into VEB Pentacon 1970. Due to its vicinity with the German camera and optics industries in Saxony (Dresden, etc.), Meyer-Optik was from an early stage heavily involved with manufacturing lenses for all kinds of cameras, but the company’s real golden age started with the advent of interchangeable lens cameras, where Meyer-Optik was uniquely placed to offer a cost-effective alternative to premium brands such as Carl Zeiss Jena.
Meyer-Optik was pronouncedly a camera lens manufacturer and never had serious ambitions for pursuing horizontal integration (diversifying into cameras and other photo gear). Instead, MOG pursued a vigorous strategy of seeking economies of scale, combined with never putting too many eggs in any basket – typically Meyer-Optik would choose which designs to put into production based on being able to cover as many platforms/mounts with one basic design. As a result, many early MOG designs were made available for a wide range of camera platforms. Later, as the number of alternative platforms diminished, that strategy had to go in favour of a strong focus on M42 and (to a somewhat lesser extent) Exakta. Even so, throughout the 60s, MOG vigorously pursued innovative designs and could by the end of the decade proudly offer a wide range of high-quality, cost effective designs.
When the lens maker Meyer-Optik was then merged with the camera maker Pentacon, it became obvious that the role the company (and its product portfolio) was intended to play was to aid Pentacon in its designs of gaining a significant global market share in the price-conscious consumer segment (and help bring hard currency to the G.D.R). Instead of focusing on continued optical innovation, the new overlords were more keen on redesigning lenses for greater economy and easier manufacture. As a result, the pace of optical innovation at MOG/Pentacon fell drastically, and very few new designs or significant redesigns were to be forthcoming in the next two decades.
However, the Meyer-Optik Oreston comes from what would later be known as the golden decade of Meyer-Optik. While the names Meyer-Optik and Oreston were soon to disappear from view, the design work done at Meyer-Optik would turn out to have an impactful legacy.
The Trioplan was manufactured for more than 30 years, and during one world war and one photographic revolution. Hence, it is almost surprising that it did not change more than it did.
The Trioplan design has its origins in triplet (fixed) lenses for medium format. At the time when interchangeable lens cameras (such as the Kine Exakta) were introduced, the Trioplan was quickly repurposed to act as a wide-aperture short tele lens.
The original 100 mm f/2.8 Trioplan was a preset aperture lens, and was offered for a wide range of mounts (including Exakta, m42, Praktina, and others). Likewise, based on a similar basic triplet design, also a Trioplan 50/2.9 was produced. The 50-version was available both as interchangeable lens, but was also used as fixed lens on many integrated cameras.
In 1958, as an attempt to modernise the Trioplan, the Trioplan-N (this lens) was introduced. It used more modern glass types, and offered an auto aperture, but also used a 6-bladed aperture. At the time, the Trioplan-N was hailed as a major improvement in image quality. The Trioplan-N was only ever offered for the Exakta mount and only as a 100 mm version.
n.B! The following applies this lens in Exakta mount.
This lens cannot be used natively on any current SLR or dSLRs. To use it in its native environment, you will need an Exakta-mount film body. Exakta bodies were manufactured in large numbers, but most of them are no longer in a good shape. That said, procuring a workable sample should not be impossible or especially expensive.
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, the Exakta lenses are so uncomplicated that a simple ‘dumb adapter’ will do the job perfectly. Furthermore, due to the popularity of the Exakta mount, special adapters (helicoid adapters, tilt/shift adapters) are readily available. Alternatively, one can choose to daisy-chain adapters (e.g. Exakta->Canon EF; Canon EF –> mirrorless) which also opens up a wide range of speed boosters .
Using Exakta 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 Exakta lenses perfectly using a simple adapter ring.
• Nikon F, Pentax K and Minolta / Sony A dSLRs need an adapter that uses corrective optics for Exakta lenses (the difference in flange focal distances is not enough to enable reaching infinity focus without corrective optics).
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.