Zone focusing and shooting hyperfocal

Hyperfocal shooting is a subset of zone focusing. Both are very, very useful tools in the arsenal of a photojournalist or street photographer; especially so if you’re using a manual focus lens, or one with a meaningful depth of field scale engraved on it. It means that if you know what distance your subject has to be at to fill your frame correctly, you can set that and just shoot straight away when you bring the camera to your eye – a very fast way of working. It’s what I usually do when I have enough light and a wide lens on my Leica.

Let’s start with zone focusing. It’s simple if your lens has a depth of field scale:
1. Pick an aperture
2. Find the depth of field scale markings corresponding to that aperture.
They’re on the bit of the lens that doesn’t rotate.
3. There are two of them. Everything between those two marks will be inn acceptable focus. Why the hesitation around ‘acceptable’? Because sharp-at-the-100%-pixel-level defines acceptable focus, and that will vary from camera to camera – the higher your pixel density, the narrower the acceptable focus margin will be. You’ll have to experiment for your camera and find out how much (if anything) to compensate by – for some cameras, you might find you have to as much as halve the width of the gap between the two markings.

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Leica 21/1.4 Summilux-M ASPH.

Example: in the image below, the lens is focused just after 1.5m. This means the sharpest point will be at 1.5m, but if we set f2.8, objects from 1.2m to a bit over 2m will be in focus. Selecting f5.6 expands this further to 1m to 5m.

A good rule of thumb is 1/3-2/3: one third of your DOF will be in front of the focus distance, and 2/3rds behind.

Simple, right? There are a few more things to know.
1. It works best for wide-angle lenses, because they have more DOF for a given aperture. (You could zone focus with a telephoto, but you’d need a silly small aperture and probably run out of light).
2. It works best during daytime, because you’ll have enough light to stop down a bit (and thus increase your margin for error).
3. It works best if you have some practice estimating distances, because you can adjust on the fly without having to bring the camera to your eye.
4. It works best with smaller sensor cameras, because again there’s more DOF for a given angle of view (focal length equivalent) and aperture – for instance, the Ricoh GR-Digital III has a ‘snap’ mode that sets focus to certain distance; at f2.8 and 1.5m, almost everything will be in focus from 0.75cm onwards or so.
5. You can’t do it easily with modern AF lenses – those which do have DOF scales usually only give f11 and f22, which are heavily restricted by the amount of light you’ve got to work with; then the distance scale itself is short and probably not very precise, with few distances marked; lastly, there isn’t enough precision in the focusing ring. You could do it by using the AF system to focus on a distance, switch to MF, and set your aperture – but you’d have to memorize your DOF tables, which is never easy or fun.
6. Some compacts are better than others for this than others; the best kind have manual focus with a DOF indicator bar and scale – the Leica X1 and Ricoh GR-Digital series come to mind.

Let’s move on to hyper focal. The hyper focal distance is the setting beyond which everything is in focus to infinity at a given aperture. Even super-shallow DOF lenses like the Noctilux 0.95 have a hyper focal distance – but it’s probably 50m or something at f0.95. Once again, the wider the lens, the nearer the hyper focal distance will be for a given aperture. With lenses in the 28mm range, you can work at a reasonable aperture of f8 or so and have hyper focal distance at about 3m on a full frame sensor, which is great for capturing spontaneous moments in photojournalism or street photography.

There are several very useful calculators online, such as DOF Master – playing around with this will give you a good idea of which of your camera/ lens combinations is best suited to zone focusing. I personally do it with my Leica M9-P, and sometimes with the Ricoh GR-Digital; but never with the DSLRs because AF is very nearly as fast, especially on the D700. Also, beware lenses like the Olympus ZD 12/2 for micro four thirds – it might look like it has distance and DOF scales, but the focusing ring is electronically coupled, and lacks the resolution to make it truly useful. MT