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What do all of theses things mean (EF-S 17-85mm 4-5.6 IS USM.)?
i think Ultrasonic motor drive=USM but what the hell does the rest mean lol. im new to this
2 Answers
- cabbiincLv 71 decade agoFavorite Answer
EF is the mount, it's a Canon
EF-s means it will ONLY work on a crop sensor digital camera like a Rebel. It will not mount on a film camera or a full frame camera like the 5D
17-85 is the focal length. http://www.fredparker.com/vislize.htm
4-5.6 is the maximum aperture. The lens is an f/4 at 17mm and f/5.6 at 85mm. If it were a 24-70 f/2.8 (notice just one f/#) that would mean that you could achieve f/2.8 at 24m and 70mm.
IS stands for Image Stabilization and means just what it sounds like.
USM means Ultra Sonic Motor. Besides being quieter it's a fast focusing (motor wise, different camera bodies will focus "faster").
