Learn the Science of Deep Focus and Hyperfocal Distance

Hyperfocal distance is a tool often used by certain genres of photography to render an entire scene in focus. It allows you to capture the foreground through to the background, keeping the whole image sharp. But how does it work? This 12-minute video by Filmmaker IQ looks at the science behind hyperfocal distance.

Increasing the f-stop value to keep a scene in focus isn’t necessarily always the best option. Once you reach a certain point, diffraction takes hold and your photo will become soft because of the small aperture.

Instead, try focusing at the hyperfocal distance. It’s the optimum point which you can focus at, using f/8 or similar, to achieve the largest possible depth of field through the image.

If you love algebra, then you’ll enjoy this equation decoding the actual workings of hyperfocal distance:

It means that a lens with a smaller focal length has a hyperfocal distance closer to the camera. A higher f-stop also renders the hyperfocal distance closer. Finally, the same goes for a larger circle of confusion (the size a spot of light can be before it is no longer deemed “acceptably sharp”).

You can see in this clip from the video that light coming from the hyperfocal distance point is perfectly sharp, running straight through the center of the circle of confusion. But crucially, light from both double and half this distance also runs within the confines of the circle of confusion, also rendering these areas in the scene sharp.

The entire 12-minute video is quite fascinating and definitely worth watching if you want to understand the science behind this widely used concept in photography.