====== Canon Lenses FAQ ======

===== Canon Abbreviations =====

**Mounts**

  * **R-Mount** - really old thing, started to be used in 1959
  * **FL-Mount** - first really popular manual lenses mount, started at 1964.
  * **FD-Mount** - most popular old Canon manual mount, used since 1971. Compatible with FL lenses.
  * **EF-Mount** - completely new mount, focusing and aperture are controlled by lenses themselfs.
  * **EF-S Mount** - Lenses made for APS-C sensors, can not be used on old EF bodies.
  * **EF-M Mount** - Mirrorless mount used only in Canon M cameras.

**More General**

  * **L** - Abbreviation for premium lenses.
  * **I, II, etc** - indicate lens generation, usually improved and more advanced lenses have higher number.

**Auto Focus related**

  * **AFD**  - Arc-Form Drive, slowest and noisiest drive. No manual focus override. Bad for video.
  * **MM** - Micro motor, smaller focus drive, also noisy and without focus override. Bad for video. 
  * **STM** - Stepper Motor, good for slow focus changes, quite silent, good for video.
  * **USM** - Ultrasonic Motor, fast for still photos focusing, almost silent. Not very good for video.
  * **Nano USM** - latest version of ultrasonic motor, made to be almost silent and good for video.

**Stabilization**

  * **IS**  - Optical Image stabilization, in fact can differ from year to year and lens to lens.
  * **IS II** - Sometimes used to indicate advanced stabilization for newer lens.

**Special Lenses**

  * **PZ** - Lens with power zoom. Such lenses are made for video work mostly.
  * **Macro** - Lens that have small minimal focusing distance and flat focusing plane.
  * **Compact Macro** - Smaller macro lens that can not reach usual 1:1 macro dimensions, usually 1:2 only.
  * **MP-E** - Ultra Macro lens, like 5:1.
  * **TS-E** - Abbreviation for tilt-shift lenses.

**Optical Construction**

  * **SSC** - Canon brand of good elements coating. Used only on old glass, now it comes by default.
  * **DO** - Lens with at least one Diffractive Optics element.
  * **Softfocus** - Lens with element making picture dream like.

===== General Lenses info =====

We have separate page for Canon FD - [[Camera Usage::Canon FD Lenses FAQ| Canon FD Lenses FAQ]]

Feel free to contact us if you want to add info for new Canon EF.