The Canon Extender EF lenses are a group of teleconverter lenses made by Canon. These lenses are used between any compatible EF type lens and any of the Canon EOS line of cameras. When used with a compatible lens, they will multiply the focal length of the lens by a factor of either 1.4x or 2x, at the cost of decreasing the lens' aperture by 1 or 2 stops respectively. For example, using a 1.4x or 2x extender with the Canon EF 500mm f/4L IS USM would result in a 700mm f/5.6 or 1000mm f/8 lens.
Canon has released six models:
The extenders are constructed with metal bayonets, and engineered plastic ends. There are no moving parts, other than the lens latch lock. Three generations of the extenders exist: the older 1.4× and 2×, the 1.4× II and 2× II, and the 1.4× III and 2.0× III. The II versions have weather-sealing and anti-reflective surfaces inside the extender body. The optical construction of the 1.4× versions are of a five-element design. Both 2× versions use seven elements, although the optical formula of the II version is different to improve optical performance. [3] The III versions of the extenders have improved autofocus performance as well increased image quality over the II, and their front and rear elements are coated with fluorine anti-smear coating to be easier to clean. [4]
These Extender EF lenses can only be used with lenses that have a compatible mount. While all EF lenses have mount designs that can be used with EOS bodies, only lenses with accordant mounts can be used with the extender EF lenses. These lenses must have the clearance to accept the protruding lens on the extender, as well as 10 (3 extra) electronic contacts for proper electronic communication with the extender. These extra electronic contacts are used for sending the correct aperture information to the body.
When a compatible lens is used with a 1.4× or 2× extender, it will cost the lens a one or two stop decline in aperture size, respectively. Autofocus speed of any used EF lens is also affected. When used with the 1.4× extender, autofocus speed is reduced by 50%. When used with the 2× extender, autofocus speed is reduced by 75%. Image stabilization may not work on lenses that are equipped with an extender, or on certain EOS bodies.
Some EOS bodies are unable to autofocus when the maximum aperture of a lens is smaller than f/5.6. Professional-level bodies are capable of autofocusing lenses with a maximum aperture of f/8, but only with the centre autofocus point. [5] With a 2× extender a 400mm f/4 lens would have an equivalent focal length of 800mm and a maximum aperture of f/8, in which case autofocus would only be available with professional bodies. With the same converter a 400mm f/5.6 lens would have a maximum aperture of f/11 and autofocus would be disabled.
Though not specified by Canon as such, users have reported that the tilt-shift lenses in Canon's line-up can also be used with the extenders. [6] [7] [8] However, when used with an extender, the lens will not pass on the correct aperture to the camera. The focal length stored in the Exif data will also be incorrect.
The following is a list of EF lenses that are compatible with the Extender EF lenses together with their resulting focal lengths, and apertures. Also listed is the autofocus and image stabilization functionality.
| Lens | Lens with 1.4× | AF with 1.4× | IS with 1.4× | Lens with 2× | AF with 2× | IS with 2× |
|---|---|---|---|---|---|---|
| 135 mm f/2L USM | 190 mm f/2.8 |  | — | 270 mm f/4 | | — |
| 180 mm f/3.5L Macro USM | 252 mm f/5 [nb 1] | [nb 2] | — | 360 mm f/7.1 [nb 1] |  | — |
| 200 mm f/1.8L USM | 280 mm f/2.5 [nb 1] | | — | 400 mm f/3.5 [nb 1] | | — |
| 200 mm f/2.0L IS USM | 280 mm f/2.8 | | | 400 mm f/4 | | |
| 200 mm f/2.8L II USM | 280 mm f/4 | | — | 400 mm f/5.6 | | — |
| 300 mm f/2.8L USM | 420 mm f/4 | | — | 600 mm f/5.6 | | — |
| 300 mm f/2.8L IS USM | 420 mm f/4 | | | 600 mm f/5.6 | | |
| 300 mm f/4L USM | 420 mm f/5.6 | | — | 600 mm f/8 |  [nb 3] | — |
| 300 mm f/4L IS USM | 420 mm f/5.6 | | | 600 mm f/8 | [nb 3] | |
| 400 mm f/2.8L USM | 560 mm f/4 | | — | 800 mm f/5.6 | | — |
| 400 mm f/2.8L II USM | 560 mm f/4 | | — | 800 mm f/5.6 | | — |
| 400 mm f/2.8L IS USM | 560 mm f/4 | | | 800 mm f/5.6 | | |
| 400 mm f/4 IS DO USM | 560 mm f/5.6 | | | 800 mm f/8 | [nb 3] | |
| 400 mm f/4 DO IS II USM | 560 mm f/5.6 | | | 800 mm f/8 | [nb 3] | |
| 400 mm f/5.6L USM | 560 mm f/8 | [nb 3] | — | 800 mm f/11 | | — |
| 500 mm f/4L IS USM | 700 mm f/5.6 | | | 1000 mm f/8 | [nb 3] | |
| 500 mm f/4.5L USM | 700 mm f/6.3 [nb 1] | [nb 3] | — | 1000 mm f/9.0 [nb 1] | | — |
| 600 mm f/4L USM | 840 mm f/5.6 | | — | 1200 mm f/8 | [nb 3] | — |
| 600 mm f/4L IS USM | 840 mm f/5.6 | | | 1200 mm f/8 | [nb 3] | |
| 800 mm f/5.6L IS USM | 1120 mm f/8 | [nb 3] | | 1600 mm f/11 | | |
| 1200 mm f/5.6L USM | 1680 mm f/8 | [nb 3] | — | 2400 mm f/11 | | — |
| 70–200 mm f/2.8L IS USM | 98–280 mm f/4 | | | 140–400 mm f/5.6 | | |
| 70–200 mm f/2.8L IS II USM | 98–280 mm f/4 | | | 140–400 mm f/5.6 | | |
| 70–200 mm f/2.8L USM | 98–280 mm f/4 | [nb 3] | — | 140–400 mm f/5.6 | [nb 3] | — |
| 70–200 mm f/4L IS USM | 98–280 mm f/5.6 | | | 140–400 mm f/8 | [nb 3] | |
| 70–200 mm f/4L USM | 98–280 mm f/5.6 | | — | 140–400 mm f/8 | [nb 3] | — |
| 100–400 mm f/4.5–5.6L IS USM | 140–560 mm f/6.3–8 [nb 1] | [nb 3] | | 200–800 mm f/9–11 [nb 1] | | |
| 100–400 mm f/4.5–5.6L IS II USM | 140–560 mm f/6.3–8 [nb 1] | [nb 3] | | 200–800 mm f/9–11 [nb 1] | | |
| 200–400 mm f/4L IS USM (without built-in extender 1.4×) | 280–560 mm f/5.6 | | | 400–800 mm f/8 | [nb 3] | |
| 200–400 mm f/4L IS USM (with built-in extender 1.4×) | 400–800 mm f/8 | [nb 3] | | 560–1120 mm f/11 | | |
| TS-E 17 mm f/4L | 24 mm f/5.6 | [nb 4] | — | 34 mm f/8 | [nb 4] | — |
| TS-E 24 mm f/3.5L | 35 mm f/5.0 [nb 1] | [nb 4] | — | 50 mm f/7.1 [nb 1] | [nb 4] | — |
| TS-E 45 mm f/2.8 | 65 mm f/4.0 | [nb 4] | — | 90 mm f/5.6 | [nb 4] | — |
| TS-E 90 mm f/2.8 | 125 mm f/4.0 | [nb 4] | — | 180 mm f/5.6 | [nb 4] | — |
| Key | ||||||
| Autofocus: | - AF works. - AF works only with EOS bodies that can AF at f/8. - AF does not work. | |||||
| Image stabilization: | - IS works. - IS works only with supported EOS bodies (generally, bodies introduced since approximately 1995). | |||||
Canon EOS bodies that have a high density, high precision auto-focus sensor with 45 or more AF points are able to autofocus at maximum apertures of f/8. [9]
Canon EOS bodies that have Dual Pixel CMOS AF like the 70D and later models support autofocusing in Liveview mode, with maximum apertures as small as f/11. [14]
Canon EOS is an autofocus single-lens reflex camera (SLR) and mirrorless camera series produced by Canon Inc. Introduced in 1987 with the Canon EOS 650, all EOS cameras used 35 mm film until October 1996 when the EOS IX was released using the new and short-lived APS film. In 2000, the D30 was announced, as the first digital SLR designed and produced entirely by Canon. Since 2005, all newly announced EOS cameras have used digital image sensors rather than film. The EOS line is still in production as Canon's current digital SLR (DSLR) range, and, with the 2012 introduction of the Canon EOS M, Canon's mirrorless interchangeable-lens camera (MILC) system. In 2018 the system was further extended with the introduction of the EOS R camera, Canon's first full frame mirrorless interchangeable lens system.
The EF lens mount is the standard lens mount on the Canon EOS family of SLR film and digital cameras. EF stands for "Electro-Focus": automatic focusing on EF lenses is handled by a dedicated electric motor built into the lens. Mechanically, it is a bayonet-style mount, and all communication between camera and lens takes place through electrical contacts; there are no mechanical levers or plungers. The mount was first introduced in 1987.
A teleconverter is a secondary lens mounted between a camera and a photographic lens which enlarges the central part of an image obtained by the lens. For example, a 2× teleconverter for a 35 mm camera enlarges the central 12×18 mm part of an image to the size of 24×36 mm in the standard 35 mm film format.
The EOS-1Ds Mark II is a digital SLR camera body introduced by Canon Inc. in 2004. It was the top model in the Canon EOS line of digital cameras until April 2007, with a full-frame 16.7 megapixel CMOS sensor. The EOS-1Ds Mark II had the highest pixel count available in a 35mm format digital SLR at the time of its introduction until its successor was announced in August 2007. It uses the EF lens mount. The EOS-1Ds Mark II is a professional grade camera body and is large, ruggedly built, and dust/weather-resistant.
The EF 70–200mm lenses are a group of telephoto zoom full-frame lenses made by Canon. The lenses have an EF mount to work with the EOS line of cameras.
The EF 1200 mm f/5.6 L USM is a super-telephoto prime lens that was made by Canon Inc. It uses an EF mount, and is compatible with the Canon EOS camera range. It has a focal length of 1200 mm and so on a digital body with a sensor size of 22.5 mm × 15 mm, such as a Canon EOS 40D or 450D, it provides a 35 mm field of view equivalent to that of a 1920 mm lens. With a body with a sensor size of 28.8 mm × 19.2 mm, such as a Canon EOS-1D Mark IV, the field of view is equivalent to that of a 1560 mm lens.
The EF 50mm lenses are a group of normal prime lenses made by Canon that share the same focal length. These lenses are based on the classic double-Gauss lens, with the f/1.8 being a standard six-element double-Gauss with an air gap and powers between element 2 and 3 and its faster cousins adding additional elements. The 50mm focal length, when used with a 35mm film or full-frame sensor, has been widely considered to match the perspective seen by the human eye.
The EF 85mm lenses are a group of medium telephoto prime lenses made by Canon Inc. that share the same focal length. These lenses have an EF type mount that fits the Canon EOS line of cameras.
The EF 100–400 mm f/4.5–5.6L IS USM is a professional EF mount telephoto zoom lens manufactured by Canon Inc. The first version of this lens was announced in September 1998, and an updated version was announced in November 2014. It is a high performance telephoto lens most often used for sports and wildlife photography.
The EF 500mm lenses are a group of super-telephoto prime lenses made by Canon that share the same focal length.
The EOS 1D Mark III is a professional 10.1 megapixel digital single lens reflex camera (DSLR) camera body produced by Canon. The EOS 1D Mark III was announced on February 21, 2007 and is the successor of the Canon EOS-1D Mark II N and was first released in May 2007. In late 2009, the camera was succeeded by the Canon EOS-1D Mark IV. One of the main benefits of the new Mark III, over the previous models, was the added functionality of Live view, allowing users to take pictures while looking at an LCD screen. While it had the same outdated software as the older 1D series cameras, it had a much improved button layout, which is still used today. It also had improved wireless capabilities over the Mark II. The new WFT-E2 was much smaller than the previous WFT-E1 for the Mark II. The new transmitter could now also connect via a USB port. This allowed the optional addition of a GPS unit and wired PC connectivity.
The EF 300mm lens refers to a family of telephoto prime lenses made by Canon, five of which have been sold to the general public and one of which was only made on special order. The lenses have an EF type mount which fits the Canon EOS line of cameras.
The EOS-1Ds Mark III is a digital SLR camera body by Canon designed for professional photographers. The Canon EOS 1Ds Mark III is successor to the EOS-1Ds Mark II and was announced in August 2007. The camera features a full-frame 21.1 megapixel CMOS sensor with 14-bit analog/digital converters for a total colour depth of 16,384 tones per subpixel. It features a three-inch (76 mm) LCD screen, capable of "Live View," and dual DIGIC III processors allowing it to shoot at up to five frames per second.
The Nikon F-mount teleconverters are a group of magnifying lenses mounted between the lens and camera bodies using the Nikon F-mount. Currently, 1.4x, 1.7x and 2x converters are available separately; a fourth, the 1.25x, is available only with Nikon's newest 800mm supertelephoto lens.
The Canon EOS 5D Mark III is a professional-grade 22.3 megapixel full-frame digital single-lens reflex (DSLR) camera made by Canon.
The EF 200–400 mm f/4L IS USM Extender 1.4× is an EF mount super telephoto zoom lens produced by Canon. It is part of the professional L-series and functions with the Canon EOS line of cameras. The EF 200–400 mm lens features an ultrasonic motor, image stabilization and weather sealing. It is the first and only EF lens with a built-in extender.
The EF 35-105mm lens is a family of EF mount wide-to-normal zoom lenses manufactured and sold by Canon. There were three versions made. The first version was released in 1987 as an f/3.5 - f/4.5 aperture lens. The next was released in 1991 as a f/4.5 - f/5.6 aperture lens. The last version was released in 1992 as a f/4.5 - f/5.6 USM version.
The Canon EOS 80D is a digital single-lens reflex camera announced by Canon on February 18, 2016. It has the same body-only MSRP as the Canon EOS 70D, which it replaces. The camera can be purchased as a body-only, as kit with the 18-55mm IS STM lens, with the new 18-135mm IS USM lens or with the EF-S 18-200mm IS. As a part of the Canon EOS two-digit line, it is the successor to the EOS 70D and is the predecessor of the EOS 90D.
The Canon EOS 6D Mark II is a 26.2-megapixel full-frame digital single-lens reflex camera announced by Canon on June 29, 2017.
In 1989, Canon released a single lens reflex camera, the EOS-1. It utilized new technologies not found in the earlier EOS-650, in a professional level body, of which, many of its unique, distinctive characteristics are still found today in more recent versions of its series. Numerous accessories were also available to boost performance and battery life.