A&P Hyperfocal Distance

Discussion in 'Lifestyle' started by CRC, Jan 27, 2005.

  1. CRC

    CRC New Member

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    What is it and how should I use it?

    I know it has to do with getting landscape pictures in focus. Why can't I just put the focus on something way off in the distance? How is that different than focusing on the hyperfocal distance?
     
  2. TheEvil1

    TheEvil1 Hell is other people OT Supporter

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  3. mojito

    mojito New Member

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    your DOF carries 1/3 of the way in front of the plane of focus and 2/3 behind. If you focus on something way in the background, then the front won't be in focus.
     
  4. mojito

    mojito New Member

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    Stopping down past say F/16, won't help bringing in much more DOF and will start to lose sharp focus from so many aperature blades in such a small area
     
  5. hash browns

    hash browns lolcathlon champion OT Supporter

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    Hyperfocal distances are used to maximize in-focus areas.

    The way this works is, depth-of-field, how much you have in focus, and where you depth of field is gets determined by your focus point, and aperture size.

    So, the amount of depth-of-field you have is controlled by the aperture size. The smaller the aperture, the more DOF. At some point, things will start to get a little fuzzy again due to 'diffraction', but the areas are technically still in focus.

    Where your in-focus areas get positioned is controlled by your focus point. Roughly 1/3 of the in-focus area will be in front of the place you focused, 2/3rds will be behind where you focused. If you focus at infinity, that 2/3rds is behind infinity, and is effectively wasted.

    The idea of focusing at the hyperfocal point is to make the last 2/3rds of your in-focus area include infinity, so you can get most of the foreground in-focus, all the way to infinity. This means you will need to set your focus point a little bit ahead of infinity.
     
  6. CRC

    CRC New Member

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    :bowdown:

    That one sentence makes me understand it now. Thanks!
     

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