Hyperfocal distance is the focal distance of the lens at which the maximum depth of field can be achieved. When the camera is focused at hyperfocal distance, everything starting from the half of the hyperfocal distance from the camera to infinity is in focus i.e. if the hyperfocal distance is 20 meters than everything between 10 meters from the camera to infinity will be in focus.
1/3rd Rule of focus
The sharpness of an image diminishes in the areas moving away from the focal point. The reduced sharpness isn’t visible to human eyes till it reaches a certain point. The area which remains relatively sharp is called the ‘circle of confusion’. While shooting a scene where the farthest point is not at infinity, most of the photographers follow the ‘1/3rd rule of focus’. 1/3rd rule of focus states that, when the focus is set at a point, 1/3rd of area in front of that point and 2/3rd of area behind that point remain in focus. In simple terms, it means that to achieve maximum sharpness, a photographer should focus at 1/3rd of the total distance from the camera. When the farthest point of sharpness reaches infinity, than the point at which the focus should be in order to keep everything sharp, is called the hyperfocal distance.
When we focus anywhere before the hyperfocal distance, the farthest point goes out of focus. Similarly when we focus anywhere after the hyperfocal point, we lose the sharpness in the areas closer to the camera.
How to calculate hyperfocal distance
The hyperfocal distance can be calculated using several techniques. Some DSLR lenses have the distance and depth of field scale with the help of which, you can very easily calculate the hyperfocal distance. If your camera lens doesn’t have the distance and depth of field scale, you can calculate the hyperfocal distance using available online multiple tools by providing the aperture value and focal length of your camera lens. For a wider depth of field, the camera aperture should be smaller indicating a larger ‘f’ value. But, setting your camera at a very high f-value may result in diffraction which can reduce the image quality.
Use in landscape photography
Hyperfocal distance is mostly used in landscape photography where the depth of field needs to be up to infinity. While shooting a landscape, the photographer wants to keep everything in front of camera in focus. By calculating the hyperfocal distance using any of the above mentioned methods, you can achieve the desired sharpness for your image. While shooting a landscape scene, it is better to focus behind the hyperfocal distance than to focus before it.