How does USM help?

Discussion in 'Beyond the Basics' started by cbay, Oct 21, 2005.

  1. cbay

    cbay TPF Noob!

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    Hello

    I have got USM on both of my lenses and i paid the extra to have it but im not entierly sure how it helps. Please could someone explain further.
     
  2. Meysha

    Meysha still being picky Vicky

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    Does USM mean Ultra silent/sonic movement... or something like that. So basically... it's quiet.

    I think it's also faster than the normal canon focussing lenses. I'm now off to find you a proper link that actually knows what it's talking about....
     
  3. Meysha

    Meysha still being picky Vicky

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  4. LittleMan

    LittleMan TPF Noob!

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    That will give you a very crisp image when other lenses without USM won't. :)
     
  5. Meysha

    Meysha still being picky Vicky

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    Without this advanced feature of the brakes actually stopping stuff, the huuuge torque power would literally rip the lens off your camera and go rolling down the street.

    Ahhh I love the people who write these blurbs.
     
  6. LittleMan

    LittleMan TPF Noob!

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    :lmao:
     
  7. DocFrankenstein

    DocFrankenstein Clinically Insane?

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    USM
    1) Focuses faster, quieter. No buzzy noises like my 50/1.8
    2) It focuses accurately, because it can change speeds. Where non USM lenses focusing accuracy is limited by the minimal shift of the motor rotor, IE 1/3 or 1/2 a turn... USM lenses are not.

    This results is faster and accurate focus and a USM lens hunts much less than a non usm lens does, giving you opportunity to shoot easier.
     

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