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Overview of Four Thirds Lenses

Developments in advanced lens design have arguably been at the center of Four Thirds. Olympus and Panasonic conceptualized their lenses for the new imaging system from the ground up for digital photography. In particular, they chose to produce lenses that are telecentric, so that the light rays hit the digital sensor orthogonally. As a result, FT-lenses show a very high and even sharpness from corner to corner. Also, FT-lenses tend to reach a high level of contrast and sharpness already at their widest aperture, so that there is little need to stop the lens down in order to improve image quality.

Telecentricity
Telecentric design of the Olympus ZD 14-54mm[olympus]

Moreover, the relatively small sensor in FT cameras has made it possible to reduce the size and weight of 43-lenses, so that many optics are more compact than corresponding lenses for APS-C or full frame systems that provide the same angle of view. Four Thirds lenses have a format factor of 2, meaning that an FT-lens with a focal length of 25mm provides the same field of view as a 50mm lens on a 35mm-full frame camera. Moreover, the Four Thirds lens delivers a depth of field that is 2 aperture stops wider than a 35mm-full frame lens with the same angle of view, so that it is easier to get the main subject in sharp focus. On the other hand, using FT-lenses makes it more difficult to achieve a very narrow depth of field that is sometimes desired in portrait photography.

Zuiko
The collection of Olympus FT lenses[olympus]

Since the launch of the FT-system in 2003, the lens catalog expanded quickly over the following years. It grew to comprise a total of more than 50 optics with native FT-mounts. In 2008, Micro Four Thirds was created as a mirrorless camera system with an even shorter flange-focal-distance, thus making it possible to realize substantial further reductions in lens size and weight. While mFT quickly superseded FT, all FT-lenses can be operated on mFT cameras with full aperture control when using an FT to mFT adapter. However, the autofocus performance of FT-lenses will fall short of that of native mFT lenses on mFT cameras, unless the camera has on-sensor phase-detect pixels (like the OMD-EM-1) or the FT-lens has an Imager-AF module designed to work with contrast-detect autofocus systems (like the newer Olympus 2.8/25mm, 4-5.6/9-18mm, 3.5-5.6/14-42mm, 2.8-3.5/14-54mm II, 4-5.6/40-150mm, and 4-5.6/70-300mm).

Olympus released a total of 24 FT-lenses, Panasonic 4, Sigma 14, and Samyang 15. Three of the 57 optics are revised versions of earlier lenses: The Olympus 50-200mm SWD received the silent and quick Supersonic Wave Drive (SWD) autofocus motor in 2007, the Olympus 14-54mm II was upgraded with the Imager-AF module in 2008, and the Samyang 85mm was redesigned with internal focus mechanisms. Production of the original lens-versions stopped when the new designs arrived.

Olympus 35-100mm
X-Ray of an Olympus 35-100mm f/2[Oliver Waletzko]

Olympus grouped its Four Thirds lenses into three categories: Super-High Grade (SHG), High Grade (HG), and Standard Grade (SG). SHG lenses are optically excellent primes and constant maximum aperture zooms, including the world's first interchangeable f/2 zooms (the 14-35mm and the 35-100mm). They are of exceptional build quality and feature environmental seals against dust and moisture. The HG lenses are also weather sealed and provide very high optical performance, with the 12-60mm and the 50-200mm being particularly popular among enthusiast photographers for their versatility and imaging quality in a compact package. The SG lenses lenses are affordable, highly portable optics that nevertheless can offer very high optical performance. For example, the 9-18mm or the 35mm Macro are very well regarded as quality lenses at budget prices.

None of the Sigma or Samyang lenses were custom-made for FT, but represent modified versions of their APS-C or full frame lens offerings. They do not provide a telecentric design, but as they are conceived to cover a larger imaging circle, only the central, "sweet spot" of the lens is used on FT-cameras, so that aberrations towards the borders and edges of the projection frame are not visible. The Sigma lenses support autofocus, while the Samyang offerings (also sold under the Rokinon brand name) require manual focusing.

Due to the relatively short flange-focal-distance of 38.67mm, lenses from many other camera systems can be mounted and used on FT-cameras via adapters. These adapters (see here on ebay) are purely mechanical devices that do not transmit any exposure or focusing information between the lens and the camera, so that aperture and focus have to be set manually. However, some adapters have a "dandelion" chip installed, which reveals lens-specific EXIF data to the camera, makes it possible to use AF confirmation, and indicates the correct focal length, so that the in-body Image Stabilization can work properly. Adapters corresponding to lenses for Olympus OM, Leica R, Nikon F, Minolta MD, M42, Pentax K, and Yashica/Contax exist. There are also adapters for Canon FD lenses, but these adapter-lens combinations do not achieve infinity focus (as the flange-focal-distance of Canon FD is only 3.3mm longer than FT, and a sufficiently robust adapter needs to be thicker), so that they are mainly of interest for macro photography. Also, the bayonet mount and flange distance of Konica AR lenses is very similar to FT and some photo enthusiasts have converted Konica Hexanon lenses for use on FT-cameras.

Below is a grouped listing of all lenses with a native Four Thirds mount and their core specifications. The manual Peleng 3.5/8mm fisheye lens (here on ebay), which has been quite popular with Four Thirds users, is not listed, as it is, in fact, an M42 lens that is mounted onto FT-cameras via an adapter. It is, thus, similar to legacy lenses and stricly speaking not a native FT-lens.

Headline Specifications of Four Thirds Lenses
Wideangle Focus
System
(type)
Front
Filter
(type)
Weather
Sealing
(y/n)
Overall
Length
(mm)
Max
Diameter
(mm)
Lens
Weight
(g)
Launch
Date
(year)
Launch
Price
(USD)
Street
Price
(amazon)
Used
Price
(ebay)
Olympus ZD 7-14mm f/4 ED AF no YES 119.5 86.5 780 2004 1799 latest check
Olympus ZD FE 8mm f/3.5 ED AF no YES 77.0 79.0 485 2005 799 latest check
Samyang 8mm f/3.5 Aspherical IF MC Fisheye MF no no 80.0 75.0 428 2009 299 latest check
Olympus ZD 9-18mm f/4-5.6 ED AF 72 no 73.0 79.5 275 2008 599 latest check
Samyang 10mm f/2.8 ED AS NCS CS MF no no 111.4 87.0 610 2013 599 latest check
Sigma AF 10-20mm f/4-5.6 EX DC HSM AF-HSM 77 no 86.4 83.5 495 2008 479 - check
Olympus ZD 11-22mm f/2.8-3.5 AF 72 YES 92.5 75.0 485 2003 799 latest check
Samyang 12mm f/2.8 ED AS NCS FISH-EYE MF no no 78.0 77.3 510 2014 499 latest check
Samyang 14mm f/2.8 ED AS IF UMC MF no no 101.4 87.0 560 2010 399 latest check
Samyang 16mm f/2.0 ED AS UMC CS MF 77 no 94.7 83.0 600 2013 399 latest check
Standard Focus
System
(type)
Front
Filter
(type)
Weather
Sealing
(y/n)
Overall
Length
(mm)
Max
Diameter
(mm)
Lens
Weight
(g)
Launch
Date
(year)
Launch
Price
(USD)
Street
Price
(amazon)
Used
Price
(ebay)
Olympus ZD 12-60mm f/2.8-4 SWD AF-SWD 72 YES 98.5 79.5 575 2007 999 latest check
Olympus ZD 14-35mm f/2.0 SWD AF-SWD 77 YES 123.0 86.0 915 2005 2299 latest check
Olympus ZD 14-42mm f/3.5-5.6 AF 58 no 61.0 65.0 190 2006 249 latest check
Olympus ZD 14-45mm f/3.5-5.6 AF 58 no 86.5 71.0 285 2005 299 - check
Panasonic-Leica 14-50mm f/2.8-3.5 D Vario-Elmarit OIS AF 72 no 103.0 79.0 490 2006 999 latest check
Panasonic-Leica 14-50mm f/3.8-5.6 D Vario-Elmar OIS AF 67 no 93.3 75.0 434 2007 699 latest check
Olympus ZD 14-54mm f/2.8-3.5 AF 67 YES 87.5 73.5 435 2003 499 - check
Olympus ZD 14-54mm f/2.8-3.5 II AF 67 YES 88.5 74.5 440 2008 599 latest check
Olympus ZD 17.5-45mm f/3.5-5.6 AF 52 no 70.0 71.0 210 2005 199 - check
Sigma AF 18-50mm f/2.8 EX DC Asp. IF AF 67 no 84.1 74.1 445 2006 449 - check
Sigma AF 18-50mm f/3.5-5.6 DC AF 58 no 67.8 67.5 270 2004 149 - check
Samyang 24mm f/1.4 ED AS UMC MF 77 no 103.0 83.0 680 1905 669 latest check
Sigma AF 24mm f/1.8 EX DG Aspherical Macro AF 77 no 87.9 83.6 520 2006 549 - check
Panasonic-Leica 25mm f/1.4 D Summilux AF 62 no 78.0 75.0 510 2007 1099 latest check
Olympus ZD 25mm f/2.8 AF 43 no 23.5 64.0 95 2008 249 latest check
Sigma AF 30mm f/1.4 EX DC HSM AF-HSM 62 no 59.0 76.6 430 2006 449 - check
Superzoom Focus
System
(type)
Front
Filter
(type)
Weather
Sealing
(y/n)
Overall
Length
(mm)
Max
Diameter
(mm)
Lens
Weight
(g)
Launch
Date
(year)
Launch
Price
(USD)
Street
Price
(amazon)
Used
Price
(ebay)
Panasonic-Leica 14-150mm f/3.5-5.6 D Vario-Elmar OIS AF-XSM 72 no 90.4 78.5 520 2007 1699 latest check
Sigma AF 18-125mm f/3.5-5.6 DC IF AF 58 no 107.0 77.0 405 2004 349 - check
Olympus ZD 18-180mm f/3.5-6.3 AF 62 no 84.5 78.0 435 2005 499 latest check
Tele Prime Focus
System
(type)
Front
Filter
(type)
Weather
Sealing
(y/n)
Overall
Length
(mm)
Max
Diameter
(mm)
Lens
Weight
(g)
Launch
Date
(year)
Launch
Price
(USD)
Street
Price
(amazon)
Used
Price
(ebay)
Samyang 35mm f/1.4 AS UMC MF 77 no 116.8 83.0 720 2011 449 latest check
Olympus ZD 35mm f/3.5 Macro AF 52 no 53.0 71.0 165 2005 229 latest check
Sigma AF 50mm f/1.4 EX DG HSM AF-HSM 77 no 73.7 84.5 530 2008 499 - check
Samyang 50mm f/1.4 AS UMC MF 77 no 80.0 81.6 545 2014 499 latest check
Olympus ZD 50mm f/2.0 Macro AF 52 YES 61.5 71.0 300 2003 499 latest check
Samyang 85mm f/1.4 Aspherical MF 72 no 80.0 78.0 522 2008 299 - check
Samyang 85mm f/1.4 AS IF UMC MF 72 no 80.0 78.0 520 2013 399 latest check
Samyang 100mm f/2.8 ED UMC MACRO MF 67 no 128.4 72.5 715 2015 599 latest check
Sigma AF 105mm f/2.8 EX DG Macro AF 58 no 95.0 74.0 450 2006 799 - check
Samyang 135mm f/2.0 ED UMC MF 77 no 127.4 82.0 830 2015 599 latest check
Olympus ZD 150mm f/2.0 ED AF 82 YES 150.0 100.0 1610 2004 2499 latest check
Sigma AF 150mm f/2.8 EX DG APO HSM IF Macro AF-HSM 72 no 137.0 79.6 895 2006 729 - check
Olympus ZD 300mm f/2.8 ED AF 112 YES 285.0 127.0 3290 2003 6999 latest check
Samyang 300mm f/6.3 ED UMC CS MF 58 no 81.4 64.5 285 2013 299 latest check
Tele Zooms Focus
System
(type)
Front
Filter
(type)
Weather
Sealing
(y/n)
Overall
Length
(mm)
Max
Diameter
(mm)
Lens
Weight
(g)
Launch
Date
(year)
Launch
Price
(USD)
Street
Price
(amazon)
Used
Price
(ebay)
Olympus ZD 35-100mm f/2.0 ED AF 77 YES 213.5 96.5 1650 2005 2499 latest check
Olympus ZD 40-150mm f/3.5-4.5 AF 58 no 107.0 77.0 425 2005 499 - check
Olympus ZD 40-150mm f/4-5.6 ED AF 58 no 72.0 65.5 220 2006 279 latest check
Olympus ZD 50-200mm f/2.8-3.5 ED AF 67 YES 157.0 87.0 1070 2003 1199 - check
Olympus ZD 50-200mm f/2.8-3.5 ED SWD AF-SWD 67 YES 157.0 86.5 1145 2007 1199 latest check
Sigma AF 50-500mm f/4-6.3 APO EX DG HSM AF-HSM 86 no 218.5 95.0 1840 2006 1099 - check
Sigma AF 55-200mm f/4-5.6 DC AF 55 no 92.5 71.5 330 2004 159 - check
Sigma AF 70-200mm f/2.8 II EX DG HSM Macro AF-HSM 77 no 189.8 86.5 1385 2008 799 - check
Olympus ZD 70-300mm f/4-5.6 ED AF 58 no 127.0 80.0 620 2007 399 latest check
Olympus ZD 90-250mm f/2.8 ED AF 105 YES 276.0 124.0 3270 2005 5999 latest check
Sigma AF 135-400mm f/4.5-5.6 DG AF 77 no 189.0 83.5 1280 2006 749 - check
Sigma AF 300-800mm f/5.6 EX DG APO HSM IF AF-HSM no no 544.0 165.5 5880 2006 7999 - check

Olympus as the lead company within the Four Thirds consortium used to publish a lens roadmap to give FT users some visibility on upcoming releases. All the envisioned lenses were launched, except one. A 100mm high-grade macro lens featured over several years on the roadmap. Yet, that lens never materialized.

lens schedule
FourThirds-roadmap (2008) with 100mm macro-lens[olympus]

Further Reading

As mentioned earlier, all FT lenses can be mounted on and used with m43 cameras. Corresponding adapters are available from Olympus, Panasonic, or third party manufacturers. Moreover, if you are interested in how a particular camera-lens combination looks like, check out the simulation tool at four-thirds.org. Finally, if the terminology and jargon around Four Thirds seems overwhelming, have a look at the Four Thirds glossary for explanations of key terms.