There are simply too many terms/abbreviations used to describe the specifications of a piece of glass. We try to compile everything that we know and we can find in the Internet. Please do comment if there’s a new term found.
And the term used may differ from one brand to another one. Just like in cars, there are DVVT, VVT-i, CVVT or VVT but they all actually perform similarly in the end result.
Learning by examples
Canon EF-S 55-250mm f/4-5.6
55-250mm is the focal length of the lens which implies that it has variable focal length which makes it a zoom lens as well. At the wide end (55mm), the maximum aperture size is at f/4 while in the tele-end, the maximum aperture size being at f/5.6.
Note that the focal length shown on all lenses are of 35mm (full-frame equivalent). You will need to multiply it with the crop factor when you are shooting with crop body to get the effective focal length.
For this case, the Canon EF-S 55-250mm can only be fitted on 1.6x crop factor body thus we will get a effective focal length of 88-400mm (after a multiplication of 1.6).
Nikon’s crop body has a factor of 1.5x. Canon’s crop body has a factor of 1.3x and 1.6x. Olympus’s crop factor is 2x.
This is a Canon made lens. It is classified in the EF-S category.
There are many terms used for Canon, and here’s the widely seen ones.
- EOS –Electro Optic System: Canon’s current SLR camera system which was introduced in 1987.
- EF – Electronic Focus: Canon’s current standard lens mount designation. It is compatible with all EOS bodies.
- EF-S: Lens mount designation for Canon’s APS-C (1.6x Crop factor) DSLRs.
- IS – Image Stabilization: Canon’s optical based stabilization system.
- L – Luxury: The designation that Canon gives to its professional range of lenses. Normally one can easily tell from its red ring around the barrel or if the lens body is in while color.
- MP-E – Macro Photo Electronic. Specialised Canon lenses designed for macro photography. MP-E lenses are manual focus and E (Electronic) refers to the electronic aperture control.
- T/S (TS-E) – Tilt/Shift. These are the lenses that can be shifted and tilted to control the plane of focus and correct perspective distortion. Used especially for architectural and studio works.
- UD – Ultra-Low Dispersion Glass: Special glass used for correction of chromatic aberration.
- USM – Ultrasonic Motor: Auto focusing motor that offers fast and silent focusing using piezoelectric elements. There are two types;
- Micro–USM: Low-cost but slower, does not support fulltime manual focus.
- Ring–USM: Faster and features fulltime manual focus override without switching off AF.
Credit to photolectic for the Canon abbreviations list.
Nikkor AF-S 50mm f/1.4G
This is a prime lens as the focal length is fixed at 50mm. The aperture size is at f/1.4. Nikkor is the branding term used by Nikon corporation to name its lens line-up. AF-S implies that the lens has built-in focusing motor. G implies that it does not have aperture control ring on it.
And this is the commonly used terms for Nikon.
- AF-S: AF-Silent Wave Motor. Lens with built-in focusing motor. Some AF-S allow manual focusing override. All AF-S lenses are AF-D.
- DX: As with Canon EF-S lenses, DX lenses are optimised for cameras with smaller sensors. They will fit on other cameras but this is not recommended.
- G : No aperture ring. Aperture is adjusted electronically by the camera body.
- VR: Vibration Reduction : Nikon’s version of Canons IS system, designed to cut down on the effects of hand shake.
- Silent Wave Motor: Silent Auto focusing (as Canons USM)
- DC: Defocus-image Control that adjusts the spherical aberration and therefore the blur giving rounded defocussing effect often used in portraiture.
- ED: Extra-low Dispersion glass. Gives superior sharpness and optimal colour by correcting the differences between the angles that blue and red light travel in as they pass through the lens.
Further reading
If you would like to learn more about the lens technology and how they name them, it is recommended that you spend some time on the links below. They offer great guide!
Canon, Nikon, Sigma, Tamron camera lenses abbreviations by squidoo.com
Making Sense of Lens Acronyms (Nikon) by bythom.com
