by Tony Sweet
Prerequisite: Hyperfocal focusing is a function of wide-angle lenses, where there is a "near-far" relationship. Longer lenses are not designed for achieving deep depth of field.
Long lenses are designed for a shallow depth of field and quick fall-off after the point of focus. That is why lenses 400mm and longer are shot wide-open a great deal of the time. Wide-angle lenses in the 20mm to 35mm range are the tools for hyperfocal focusing.
In order to get the sharpest images possible, some photographers logically focus their lenses at infinity, expecting automatic infinite sharpness. When viewing their images, they then discover that the foreground material is out of focus. How is this possible? Doesn't "infinity" mean that everything will be sharp?
Well, not exactly. At f/22, in the full frame, 1/3 in front of your point of focus and 2/3 behind your point of focus will be sharp. It's a variation of the "Rule of Thirds." Rather than focusing in the center (auto-focus) or at the furthermost element in the scene ("infinity" focusing), you focus at the lower third "line" of the frame, not of the scene.
For example, when focusing at "infinity," 1/3 in front and 2/3 behind (which goes beyond the frame) will be sharp, therefore a very soft foreground. When focusing using auto-focus, 1/3 in front and 2/3 behind the point of focus will be sharp, rendering a soft foreground, although not as soft as when focusing at "infinity."
If your lens has a depth of field scale, set the focusing mark on the lens to the distance indicated below the f/stop selected. Do not re-focus the lens once the hyper-focal distance is set. It will be out of focus. Pressing the depth of field preview button (if you have one) will pop the entire image into sharp view. Sharp focus will exist from 1/2 the distance from the lens to the hyper-focal distance into infinity. Sounds complicated, but it's really not.
Here's an example: A 20mm lens at f/22 is set to 2.8 feet. The resulting depth of field will be from (1/2 of 2.8 feet) 1.4 feet to infinity.
Here's another: A 28mm lens at f/16 and set to 8 feet. The depth of field is from 4 feet to infinity.
And here's a reference chart:
| Lens | f/11 | f/16 | f/22 |
| 20mm | Set focusing mark on lens to 5.6 ft. | Set focusing mark on lens to 4 ft. | Set focusing mark on lens to 2.8 ft. |
| 24mm | Set to 8 ft. | Set to 5.6 ft. | Set to 4 ft. |
| 28mm | Set to 11 ft. | Set to 8 ft. | Set to 5.6 ft. |
| 35mm | Set to 16 ft. | Set to 11 ft. | Set to 8 ft. |
NOTE: If your lens has NO depth of field scale, then focus 1/3 from the bottom of the frame for the maximum depth of field.
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