Tip Thursday: Hyperfocus

Hyperfocus is a method to take advantage of lens settings and attributes to maximize the amount  of in focus area in a photograph. This is especially important in landscape work where a sharp foreground and background are needed. This takes into account that depth of focus is generally 1/3 in front and 2/3 in back of the point of focus.

In other words if you just set focus to infinity you would lose the 2/3 behind the point.

In the old days of manual cameras and manual focusing all lenses came with a distance scale AND a depth of field scale. With the advent of MODERN autofocus lenses these have sadly been left off. Since most lenses used today lack a DOF scale, there’s a table on the webpage mentioned at the end of this article that shows the hyperfocal distance for different lens and f-stop combinations. The figures have been calculated mathematically. If your lens has a distance scale but lacks a depth of field scale, you can use this table to set your lens to the hyperfocal distance required.

Hyperfocal focusing is based on the fact that depth of field typically extends 2/3 behind the point focused on and 1/3 in front, but if you focus on infinity, the depth of field behind is completely wasted. You can make use of it if you refocus, putting the infinity mark (an “8″ on its side) on the focusing ring against the aperture set on the depth of field scale (this is known as the hyperfocal point). If, for example, you set a 28mm lens to f/11 and focus on infinity, everything from about 9 feet (2.5m) to infinity will be sharp. Align the infinity mark against the “11″ position to give hyperfocal focusing and the depth of field now extends from 4 feet (1.2m) to infinity, which is essential if you want foreground interest to be pin-sharp. If you set your lens to f/16 and rotate the focus barrel to place the infinity mark over the “16″ position, then reading the scales shows that everything between just under 3 feet to infinity will be sharp.

The Hyperfocal distance is the that point above the central mark on the depth of field scale when the infinity mark has been put over the required f-stop mark on the depth of field scale. In the case of the 28mm lens at f/11, that’s 9 feet / 2.5m. At f/16, the hyperfocal distance would be 5 feet. Remember that the hyperfocal distance will be different for lenses of different focal length and different f-stops.

Don’t forget that the wider the angle of a lens, the shorter its focal length and the deeper its depth of field. So, as an example, an 18mm lens will have deeper (longer) depth of field than a 105mm. Also, the smaller the aperture you use the greater the depth of field; i.e. for a lens of any given focal length, there’s more depth of field with it at f/16 than at f/4, for example.

See the chart HERE

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