Outdoor Focus Autumn 2019 | Page 15

THE JOY OF PRIMES David Taylor extols the virtues of the fixed focal length prime lens T he path of least resistance is a path that it’s all too tempting to follow. Take buying a lens for a DSLR or mirrorless camera, for example. The path of least resistance would be to buy a zoom lens. And why not? Zoom lenses are incredibly useful tools that make life far easier for the photographer. The biggest advantage of a zoom lens is of course the fact that the focal length can be altered. This makes it easier to create a variety of different compositions with a simple twist of the zoom ring, often without moving position at all. Another advantage of a zoom lens is that it cuts down the need for tedious lens swapping. (Which has the added advantage of reducing the risk of the exposed sensor getting dusty.) The ultimate in convenience is the ‘superzoom’, a lens with a huge focal length range; from wide-angle at one end to telephoto at the other. For a lot of photographers a ‘superzoom’ is the only lens they ever need. And of course zooms reduce the number of lenses that need to be packed into a camera, freeing up space for important stuff such as a plentiful supply of sandwiches. So that’s settled then, zooms are the best things since sliced bread? Actually… not so fast. There’s another type of lens that should be given serious consideration: the prime lens. A prime lens is one that has a fixed focal length, such as 35mm, 50mm, or 100mm. To cover the focal range of a typical zoom requires two, three even four different prime lenses. This makes buying primes a potentially more expensive option. It also means changing lenses more frequently. And, there’s a greater chance that the wrong lens is fitted just when the photographic opportunity of a lifetime presents itself. Oh, did I mention that it’s harder work using primes? Rather than turning a zoom ring, a photographer may need to physically move to achieve the perfect composition. Imagine that. Oddly enough though that’s the beauty of a prime lens. The relative inconvenience of a prime lens forces a photographer think about his or her photography more. On the upside, with practise it quickly becomes easy to ‘see’ compositions that suit a particular prime lens. A photographer can become so attuned to the characteristics of a prime lens that he or she can compose a shot even before picking up the camera. Prime lenses have one other big advantage over zooms. Zoom lenses are optically more complex than primes lenses, and so have far more compromises in their design. The biggest compromise is the aperture range, with zooms lenses lumbered with a relatively small maximum aperture - which may even vary as the lens is zoomed through its focal range. (It is possible to buy zooms with large maximum aperture, but these lenses tend to be both heavy and very, very expensive). Prime lenses on the other hand generally have large maximum apertures - f/1.4, f/1.8 and so on. This is makes them particularly useful when shooting in low-light conditions - allowing faster shutter speeds and helping the camera’s AF system remain fast and accurate, or when limiting depth of field is a key aesthetic decision. Personally I like primes lenses and always have one or two in my camera bag. It’s worth it, even if it does mean going hungry later in the day. Shot with a 55mm prime lens at an aperture f/1.8, this is the sort of soft, limited depth of field image that can be tricky to shoot with a zoom autumn 2019 | Outdoor focus 15