With our most recent visit to Lebanon, I had a chance to play around with hyperfocal distance. Ever since I started to consider getting into underwater video, I've been fascinated by the this theory.
To oversimplify a complicated theory, hyperfocal distance is the focal distance at which you set your camera for a given aperture and focal length in order to achieve the maximum depth of field. It will extend from a certain point in front of the camera until infinity. The advantage of this theory is that as long as everything in your picture is more than the minimum distance then everything should be in focus. There are a glut of apps out there that will help you calculate your hyperfocal distance. Just simply search for "hyperfocal" and you will find them. This approach is incredibly helpful when working with underwater video as it allows you to set your focus and simply concentrate on recording and framing and not dealing with focusing knobs etc.
During our last trip to Byblos, I decided to play around with this theory and apply it to photography. I set my camera to f11 and my focal distance to 0.8m. This meant that everything from 0.3m to infinity would remain in focus as I took pictures. Since my camera was set to back button focus and manual mode I simply had to pull the shutter release button. I found it a easy and effect way of taking photos that kept everything in focus while giving you complete control over your exposure. I would think that this would be effective in a situation where there is limited change in light. Variable light would require a much more complicated approach. In any case, here are some samples from the day.