Focusing at Hyperfocal Distance

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Today’s Question: Would focusing at the hyperfocal distance help in this case [of a photographer wanting to maximize depth of field for a scene]?

Tim’s Quick Answer: Yes, if your goal is to maximize depth of field for a scene, setting the focus for a lens to the hyperfocal distance will provide an optimal result, all other things being equal.

More Detail: In an Ask Tim Grey eNewsletter last week I addressed a question from a photographer who was trying to understand which lens aperture setting to use when focusing from a distance. The implication was that greater (or maximum) depth of field was desired.

The hyperfocal distance is the closest distance you can focus on while still retaining acceptable focus at infinity. In other words, all other things being equal, if you set the focus distance at the hyperfocal distance, you’ll have the maximum possible depth of field for the scene.

The key is to actually determine what the hyperfocal distance is for a given set of circumstances. This can be especially challenging since the hyperfocal distance will change based on changes in lens focal length or aperture setting.

In fact, the example scenario I defined in my previous answer on this subject was chosen as an illustration of focusing at hyperfocal distance. I had used the example of a 200mm lens on a given camera, with the lens aperture set to f/8 and a subject at a distance of about one-quarter mile. With these settings, it happens that the hyperfocal distance would be 497.3 yards, which is just over one-quarter of a mile.

If you are using a calculator (such as a smartphone app) to calculate depth of field, that calculator probably already provides an indication of the hyperfocal distance. Setting the lens focus at that point would yield maximum depth of field.

Of course, the bigger challenge in all of this is that with most lenses it is not very easy to set focus at a specific distance. That said, calculating the hyperfocal distance can be helpful in terms of providing a good sense of what is possible in terms of overall depth of field. For example, with a 100mm lens set to an aperture of f/22 but focusing on a subject three feet away from the lens, the hyperfocal distance would be about 135 feet.

In other words, it is impossible to achieve enough depth of field so that the subject close to the lens is in focus, while focus is also maintained at infinity. By calculating depth of field (and thereby obtaining hyperfocal distance) under a variety of circumstances, you’ll get a better sense of when you are able to achieve greater depth of field, and when it will be impossible to achieve the desired depth of field with a single capture.