Hyperfocus

Hyperfocal settings allow you to get the maximum depth of field from a lens. That means getting the most in focus such as in this image.

 The leaves in the foreground are only inches away from the lens and everything else beyond is in acceptable focus. 

The hyperfocal distance setting is the distance at which you focus the lens. And when that is done everything from half way to the focal point to infinity will be in acceptable focus.

There are online calculators, smart phone programs, printable reference cards and probably other methods of determining the hyperfocal setting. But there are problems with them. The biggest issue is that modern lenses do not have good distance scales with DOF markings like the old lenses do.

Focus scale on an old Nikon lens. The DOF markings are color matched to the apertures.

Some modern AF lenses have no distance scale at all. And even if your AF lens does have a distance scale the markings and spacing makes it impossible to preset accurately. Add to that, there's no way to check at what distance you are focused in the camera. So all you can do is estimate a point at the right distance and focus on that.

Why go thru all that effort of charts/programs etc just to SWAG it in the end? I just guesstimate it. Starting from 50mm. If you have an APS-c sensor camera the hyperfocal distance is approximately equal to half the lens's focal length when the aperture is set to f/16. If you have a full frame camera the hyperfocal distance is approximately equal to half the lens's focal length when the aperture is set to f/11. 

If you halve the aperture setting you double the hyperfocal distance.
If you double the focal length the hyperfocal distance doubles as a ratio of the focal length. (i.e. .5x at 50mm 1x at 100mm, 2x at 200m)
And the opposite is also true. (i.e. .25x at 25mm)

APS-c example:
50mm lens @ f/16 the hyperfocal setting is ~25ft, DOF 12ft to infinity. 50mm lens @ f/8 the hyperfocal setting is 50ft, DOF 25ft to infinity. 

100mm lens @f/16 the hyperfocal setting is ~100ft. equal to the focal length
200mm lens @f/16 the hyperfocal setting is ~400ft. twice the focal length
25mm lens @ f/16 the hyperfocal setting is ~6ft. one quarter the focal length


Another, perhaps easier way, of looking at it is to think of the hyperfocal distance being the same as the focal length as a percentage of the focal length. I know that makes no sense so I'll give examples for f/16(crop)/f/11(full frame). Using a 10mm lens the hyperfovcal distance is ~10% of the focal length (i.e. 1ft). Using a 25mm its ~25% of the focal length (6ft). 50mm=50%of 50(25ft). 100mm=100%(100ft). 200mm=200%(400ft), and so on.


Knowing this you can quickly estimate the hyperfocal setting, pick a point at that distance to focus on and go. However, when estimating the point to focus on, estimate long. If you focus beyond the hyperfocal distance you loose a little DOF at the near end but it does not affect infinity focus. If you focus in front of the hyperfocal distance you gain a little DOF at the near end but you loose A LOT at the far end.

And now, let me make it even easier. If you are using a lens longer than ~ 50mm or have a camera with a sensor smaller than APS-c it's not of much benefit to even bother with. And it's not of much benefit if you are not trying to maximize DOF starting very close to the camera. In those cases just focus 1/3 of the way into the scene, or "beyond the hyperfocal distance."

 

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