You are a beginner in photography and your brand new camera and lens have arrived. The lens has the symbols DO and IS on it. What on earth do these symbols mean? How about TS-E, UD, DC, DX, RF and so on?

Well, we have put together a comprehensive list of brands, their symbols and what they mean, it is all explained below.

Canon

• DO = Diffractive Optics (DO lenses have a green ring)
• EF = Electronic Focus
• EF-S = The S stands for "short back focus"
• FD = Canon manual focus (before EF)
• FT-M = Full Time Manual Focus
• IS = Image Stabilization
• L = Canon Professional Optics (L lenses have a red ring)
• TS-E = Tilt and Shift Lenses
• UD = Ultra Low Dispersion Elements
• USM = Ultrasonic Motor
• STM = Stepping Motor

Nikon

• AF-D = D-series communicate subject distance info to the camera to aid ambient light/flash metering
• AF-I = Lenses with an integrated coreless motor to facilitate faster AF in telephoto lenses
• AF-S = Autofocus lenses with an integrated SWM (Silent Wave Motor)
• CRC = Close Range Correction
• DC = Defocus Control
• DX = Digital only lenses designed for crop bodies
• ED = Extra Low Dispersion Glass
• G-Series = Optics with no aperture ring
• IF = Internal Focusing
• IX = Lenses designed for use with Pronea-Series APS SLRs
• PC = Perspective Correction
• RF = Rear Focus
• SWM = Silent Wave Motor
• VR = Vibration Reduction

Sigma

• APO = Apochromatic Lenses
• ASP = Aspherical Elements
• DC = Lenses for APS-C bodies only
• DF = Dual Focus (push/pull clutch)
• DG = Lenses for FF bodies
• ELD = Extraordinary Low Dispersion
• EX = Professional Optics
• HSM = Hypersonic Motor
• IF = Inner Focus
• OS = Optical Stabilisation
• RF = Rear Focus
• SLD = Super Low Dispersion

Tamron

• AD = Anomalous Dispersion
• ASL = Aspherical Elements
• Di-II - Lenses for APS-C bodies only
• IF = Internal Focusing
• LD - Low Dispersion Glass
• SP = Super Performance Lenses
• VC = Vibration Compensation
• XR = Smaller and less bulky lenses

Tokina

• AS = Aspherical Elements
• AT-X = Advanced Technology Extra
• FC = Focus Clutch
• IF = Internal Focusing
• SD = Super Low Dispersion Glass

Sony

• DT = Lenses for APS-C bodies only
• SWM = Sonic Wave Motor
• STF = Smooth Trans Focus
• T* = Originally developed for cine cameras
• ZA = Designates Carl Zeiss lenses for Sony Alpha lens mount

Pentax

• A = Manual Focusing Lenses
• AL = Aspherical Lens
• DA = Digital-only Lenses
• DA* = Digital-only Lenses (sealed)
• ED = Extra Low Dispersion
• FA/FA-J = Lenses with no aperture ring
• IF = Internal Focusing
• SDM = Supersonic Motor
• SMC - Super Multi-Coated Lenses

Konika - Minolta

• AD = Anomalous Dispersion Elements
• APO = Apochromatic Lenses
• DT = Lenses for APS-C bodies only
• G-Series = Minolta`s Professional Lenses
• STF = Smooth Trans Focus
• SWM = Sonic Wave Motor

Olympus

• 4/3 = Four Thirds System
• ASP = Aspherical Elements
• ED/SED = Extra Low Dispersion Glass
• OM = Manual Focusing SLR System