Different manufacturers use very different abbreviations to describe the technology used in their lenses even if the technology itself is quite similar. Some abbreviations can be difficult to understand and easily mixed up. We’ve already covered Nikon lens abbreviations. This article will help you understand Canon lens naming terminology.
Table of Contents
1) Canon Lens Format Abbreviations
- EF – this is the fully electronic Canon lens mount introduced back in 1987. Lenses marked with EF are compatible with all Canon EOS cameras, digital and film, and are designed to cover up to a 35mm full-frame image circle. However, they are designed for DSLR-style cameras, and using them on Canon’s mirrorless cameras requires the addition of an adapter.
- EF-S – the only difference between Canon EF and EF-S lenses is that the latter has been designed for Canon DSLRs cameras with APS-C sensors, such as the Canon EOS 700D. Canon EF-S lenses do not cover the full-frame image area. EF-S lenses feature a protective pin that stops these lenses from being mounted on a full-frame EOS camera.
- EF-M – a lens format specifically designed for the (discontinued) Canon EOS M mirrorless camera system with EF-M mount. (This lens mount has since been replaced by Canon’s EOS R mirrorless system.) Just like the EF-S lenses, EF-M are designed for APS-C sensor cameras. They cannot be attached to Canon DSLRs.
- RF – these are lenses for Canon’s current mirrorless system. RF lenses are mirrorless lenses, and for several years, all of Canon’s new lenses have been RF (or RF-S). RF lenses can be mounted on any Canon EOS R mirrorless camera, regardless of the camera’s sensor size. They cannot be mounted on a DSLR.
- RF-S – the only difference compared to RF lenses is that RF-S lenses are meant only for Canon’s APS-C mirrorless cameras, and they’re not meant for full-frame. (Standard RF lenses cover both APS-C and full-frame.) If you have a full-frame Canon EOS R camera, don’t get these lenses.
- FD – this is the old manual focus Canon lens mount used before 1987. Because it was not suitable for autofocus, Canon decided to switch from FD and designed the EOS system with EF mount. Canon FD is now discontinued, but still used by film photography enthusiasts. There are some cracking lenses with the FD mount and, through the use of appropriate adapters, FD lenses can be mounted on modern EOS EF cameras. Adapters with an optical glass element allow infinity focus, while simpler adapters without an additional optical element will not focus at infinity.
- FDn – the same as FD, only with no coating designation on the lens front (used SSC lens coating).
- FL – same mount as FD, but without the ability to meter at full aperture.
2) Canon Lens Class and Technology Abbreviations
- L – standing for “Luxury”, the L designation marks Canon’s top-end, professional grade lenses with the most advanced optical formulas and high quality, complex glass elements. These lenses are built to Canon’s highest standards and often feature some sort of weather protection as well as wide aperture setting. L lenses are priced according to their quality, but some are considered budget (within reason), like the 24-105mm f/4L lens. It retails for over $1100 at the moment and can hardly be considered cheap, but for an L lens, this sort of price is very acceptable. L class lenses are easily recognized by the presence of a red ring around the front end.
- SSC – Super Spectral Coating. Originally discovered by Lord Rayleigh in 1886 and enhanced by Carl Zeiss later, lens coatings made a huge impact on future optics. Basically, coating minimizes lens reflections and increases contrast. All modern Canon lenses are multicoated, so only the oldest of them have the SSC marking on the barrel.
- I, II, III – Roman numerals in the lens name describe the lens’ generation. For example, there are two Canon 24-70mm f/2.8L lenses: the first one is the Canon EF 24-70mm f/2.8L USM, and the other one is Canon EF 24-70mm f/2.8L II USM. The only difference in the name of the lenses is the “II” designation of the second lens, which means it is the newer, updated version. Both are professional, tough L-grade lenses, but with different optics and price. Generally, if a lens gains IS – which is Image Stabilization – it drops the previous numeral and should be considered a newer release.
- USM – this abbreviation means the lens is equipped with Canon’s top-end focusing motor, the ring-type UltraSonic Motor. This is a fast, quiet and powerful autofocus motor that allows full-time manual focus override. It is used in most current Canon lenses from low-cost prime lenses all the way up to exotic telephoto and L-class lenses.
- Micro USM – this autofocus motor is smaller and simpler than USM used in most Canon lenses. Like its big brother, it is fast and quiet when used in smaller lenses with lighter optical elements. There is a disadvantage, though – Micro USM does not generally allow full-time manual focus override. There are exceptions. One notable lens to feature the simpler Micro USM motor rather than full-sized ring-type USM yet allow full-time manual focus tweaking is the Canon EF 50mm f/1.4 USM. Both USM and Micro USM motors are indicated as USM on the lens itself.
- STM – Stepper Motor designed to minimize autofocus vibrations and noise during video recording, this autofocus motor has been gradually making its way into budget Canon lenses. The first lens to sport STM was the EF-M 22mm f/2 STM lens. Now, all EF-M lenses incorporate the Stepper Motor, but even some EF-S lenses have been updated, like the EF-S 18-55mm f/3.5-5.6 IS STM lens. STM lenses use fly-by-wire focusing, which means turning the focus ring does not physically move the elements, but tells the AF motor to do so.
- AFD – Arc-Form Drive is the first autofocus motor used in Canon EF lenses. It is much louder than USM motors, somewhat slower and not as quick. It also has slower reaction time so does not follow subjects as well as newer motors. There is no full-time manual focus override. If an autofocus Canon lens has no indication on its barrel what sort of AF motor is used, it is either AFD or Micro Motor.
- MM – this abbreviation stands for Micro Motor, which is the least advanced AF motor used in Canon lenses along with AFD. Basically, it is a smaller version of the AFD motor. This autofocus motor is only used in the cheapest Canon lenses, like the EF-S 18-55mm f/3.5-5.6 IS II kit zoom. This motor does not allow full-time manual focus override like the more sophisticated USM systems do. It is also somewhat louder in operation, although because the kit zoom is so light, the motor is also very small and the noise is rarely intrusive. If an autofocus Canon lens has no indication on its barrel what sort of AF motor is used, it is either Micro Motor or AFD.
- PZ – stands for Power Zoom and uses a dedicated motor to change the focal length of the lens. I believe the only Canon EF lens to use PZ is the EF 35-80mm f/4-5.6 PZ.
- IS – this is Canon’s abbreviation for optical image stabilization, or simply Image Stabilizer – a piece of technology that moves some of the lens’ optical elements to counter shake and provide sharper results when slow shutter speed is used for static subject capture.
3) Specialized Canon Lens Abbreviations
- Macro – a lens with such designation focuses down to relatively short distances and provides 1:1 magnification.
- Compact Macro – similar to regular macro lenses, Compact Macro can focus very close. As far as I know, there is only one such lens – the EF 50mm f/2.5 Compact Macro. There is a dedicated converter available for this lens that increases the working distance (distance between subject and front lens element at minimum focus) and enables 1:1 magnification for this lens. It is called the Canon Life-Size Converter EF.
- MP-E – there is only one Canon lens with such designation, and it is the Canon MP-E 62mm f/2.8 1-5x Macro lens. MP-E means very high magnification optics – this lens starts to focus at magnification where regular macro lenses run out of puff. The aforementioned lens is manual-focus only and does not focus at infinity. Instead, it can achieve magnification anywhere from 1:1 to 5:1.
- TS-E – lenses with tilt and shift adjustments used for creative portraits, landscapes, macro and architecture photography. Exotic, expensive and manual focus only.
- DO – Diffractive Optics lenses have special glass elements that bend light more than regular glass. This allows them to be smaller than regular lenses of the same parameters. A well-known Canon DO lens is the telephoto EF 400mm f/4 DO IS USM. It shares the great build quality with the L siblings, but has a green ring around the front rather than a red one.
- Softfocus – as you may have guessed, Softfocus lenses have optical formula that is meant to deliver softer results on purpose. Such lenses used to be popular decades ago among film photographers for portrait photography as they hid skin imperfections and created a “dreamy”, glowing effect. Suffice to say such lenses are no longer popular today – it is easy to achieve soft focus effect using post-processing if one should wish so. There is only one Canon EF lens with Softfocus feature, and it is the EF 135mm f/2.8 with Softfocus. It is possible to turn off the Softfocus by setting appropriate ring on the lens to the value of 0 (off), in which case the lens acts like a normal 135mm f/2.8 would.
- DS – Defocus smoothing. Lenses with this feature, like the Canon RF 85mm f/1.2 L USM DS, allow out-of-focus regions to look softer than normal. It works by applying a soft, neutral-density coating to the outer edge of one or more elements in the lens.
4) Lens Example
Now that we have all the relevant abbreviations taken care of, let’s analyze the name of an actual lens. How about the popular Canon EF 70-200mm f/2.8L IS II USM?
Based on the lens name we can easily tell that this is an expensive and professional-grade optic (L designation). As a top-quality instrument, it also features an advanced optical formula for best possible performance, including ED and Fluorite glass elements (L). Weather sealing is a possibility with L lenses and is indeed present in this particular case. It is also designed with film and digital full-frame Canon EOS cameras in mind (EF). Naturally, it can be used on crop-sensor Canon DSLR cameras, too. The lens is optically stabilized – it features Canon’s Image Stabilizer technology (IS). This is also the second version of such a lens with a stabilizer (II). Autofocus is driven by Canon’s best motor. Full-time manual focus is available, while automatic focusing promises to be very snappy and quiet (USM).