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    Focus keeps turning past hard stops? (Sigma 18-35)
    #1
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    Playing with follow focus today with camera and lens powered off. Noticed that I feel a gentle hard stop when the focus ring hits the edges of close focus or infinity focus, but then, I can keep twisting without that much effort to keep going. Is this normal, or harmful, or?


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    #2
    Senior Member Run&Gun's Avatar
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    If it's a still lens with AF, it's normal. Most still lenses focus barrels will turn continuously, because they have a clutch type system that allows the servos/motors to adjust them with the AF system, but also for the user to manually adjust it, as well. You should feel a slight stop at either end (near and far), but then you can keep turning the barrel.


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    #3
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    Quote Originally Posted by filmguy123 View Post
    Playing with follow focus today with camera and lens powered off. Noticed that I feel a gentle hard stop when the focus ring hits the edges of close focus or infinity focus, but then, I can keep twisting without that much effort to keep going. Is this normal, or harmful, or?
    Totally normal on that lens.


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    #4
    Senior Member JPNola's Avatar
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    While it does indeed sound as if the OP is talking about the stills version, be advised that the Cine versions do not have a hard-stop at infinity. They don't rotate endlessly beyond an infinity "notch" as do the stills version, but the hard-stop is beyond infinity. The reason being that such avoids the lenses having to be custom shimmed for each specific camera mount.
    Big sources matter.


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