Shopping for camera lenses can be daunting. It's easy to get caught in a whirlwind of f-stops, zoom ranges, and of course, price. But there is one lens spec that is often overlooked, but can have a significant effect on the pictures you take: minimum focus distance.
Minimum focus distance is simply the closest you can get to your subject before it goes out of focus for good. While macro lenses come to mind first when you think of getting really close to a subject, all lenses can benefit from the ability to focus extremely close-up. You can usually find the spec inscribed on the front ring of the lens, and it is listed as the distance from the focal plane (where the sensor is) to the subject. A camera or lens that focuses close is all about versatility. It gives you more options for composing a shot, and could save you from needless lens changes.
The minumum focus distance you should expect is going to vary depending on what type of camera and lens you are using. If you have a compact camera with non-interchangeable zoom lens, chances are it can focus pretty close. It might even have a little macro mode button which will help it auto-focus at close distances. Smartphone cameras also are able to focus very close, often at only a couple of inches. It is one of the few advantages they have over larger sensor cameras.
Olympus OM-D EM-1 with 12-40mm f.2.8 @ 12mm
The larger the sensor your camera has, the more distance it needs to focus (in general). Full-frame DSLRs will require the most distance, and APS-C cameras do a bit better. Micro four thirds systems are terrific at focusing close. Take the Olympus 12-40mm f/2.8 for example. It can focus as close as just under eight inches, whereas the Canon 24-70mm f/2.8, which has a similar effective focal length, requires about fifteen inches. It doesn't seem like much, but when you are sneaking in for a shot and want that up-close detail, it's disappointing when you have to back away just to focus.
Macro lenses are, of course, great for close-up work. But most macro prime lenses have telephoto focal lengths, not suitable for general use. One exception, and one of my favourite lenses ever, is the Zeiss 50mm f/2 Makro-Planar (the top image of the lime was taken using this lens). On a full-frame camera it has a 'normal' focal length, perfect for walking around with, and focuses extremely close, at about nine inches. It won't magnify your subject as much as a macro lens like the Canon 100mm f/2.8 L, but it is worlds better than the Canon 50mm f/1.4, which requires a distance of eighteen inches.
Obviously the most important specs you are going to consider when assessing a camera lens are the maximum aperture and the focal length, balanced by price. But if you are looking for versatility, take a look on the lens barrel and make sure you know how close it can focus. Being able to narrow the gap between you and your subject can provide unique perspectives that will make your images shine.