A&P why can you turn a focusing ring past infinity?

Discussion in 'Lifestyle' started by ace3, Oct 27, 2007.

  1. ace3

    ace3 mouthify my wang.

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    i apologize ahead of time for the noob question, but i'm pretty well shithoused right now.


    i was dicking around with my relatively-new 10-22 tonight, messing around with manual focus, and realized it (as well as the other lens i tried) will turn past the marker for infinite-focus.

    what would you use that for? i honestly have zero idea.

    i'm going to bed now. :o
     
  2. e.pie

    e.pie Active Member

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    in for answer :o
     
  3. ibewill

    ibewill New Member

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    buzz lightyear edition.
     
  4. mobbarley

    mobbarley Active Member

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    to compensate for any lack of neutrino production in beta decay reactions.
     
  5. White Stormy

    White Stormy Take that, subspace!

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  6. sony

    sony Active Member

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    to allow for thermal contraction/expansion as well as manufacturing tolerances

    normally you wouldn't focus beyond infinity, just to the furthest object or use hyperfocal focusing instead
     
  7. ballz

    ballz Two of 'em OT Supporter

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    infinity isn't all that far. I run that far every day.
     
  8. eighteen_psi

    eighteen_psi Active Member

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    I believe it's because it varies with focal length on zooms....and because of manufacturing tolerances and expansion/contraction of the elements and all that. Do not spin it to the max and assume its infinity, particularly on a telephoto lens. On something that wide you likely have plenty of depth of field to be OK but still... Don't assume those marking are accurate, or that the end of the ring is infinity.
     
  9. Neuro

    Neuro OT Supporter

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    infinity and beyond! :bowdown:
     
  10. Airpoppoff

    Airpoppoff Vodka > Racing F1

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    yes because of the diff focal lengths

    Fixed lenses like my 10.5 and my 50mm don't
     
  11. lilcheen

    lilcheen New Member

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    drugs are bad mmmmkay
     
  12. ace3

    ace3 mouthify my wang.

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    holy shit, when did i post this? :o
     
  13. e.pie

    e.pie Active Member

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    10-27-2007, 08:42 AM
     

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