What do the lens parameter abbreviations mean?

Question

Canon EF 50mm f/1.8 II

What does EF, II mean?

Sigma 10mm/F2.8 EX DC Fisheye HSM compatibil Canon

What do EX,DC,HSM mean?

Nikon AF-S DX NIKKOR 55-200mm f/4-5.6G ED VR

What do AF-s, Ed, Vr mean

Sigma 50-200mm/F4-5.6 DC OS HSM Canon what does DC, OS, HSM mean

Can you pease explain any other abbreviations? I really couldn't find a good resource

Answer

EF = Elecronic Focus, this is the name of Canon's autofocus mount. "II" means the second version of the lens.

EX = Sigma marketing term, denotes a higher build level. DC means the image circle is only covering APS-C ("crop").

HSM = Sigma's designation ultrasonic motor.

AF-S = Nikon's designation that the lens has the focusing mechanism in the lens, as opposed to being driven by the camera body. The mechanism is usually ultrasonic.

ED = Nikon's designation for glass with high dispersion.

VR = Nikon's designation for image stabilization in the lens ("Vibration reduction").

OS = Sigma's designation for image stabilization.

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