# A&P Hyperfocal Distance

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

1. ### CRCNew 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. ### TheEvil1Hell is other peopleOT Supporter

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3. ### mojitoNew 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. ### mojitoNew 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 brownslolcathlon championOT 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.

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