Buying a new lens is almost more exciting than buying a new camera. Sure, a new camera comes with more megapixels and useful bells and whistles, but a new lens opens up an array of creative possibilities.
Unbelievably, there are six types of lenses all vying for your attention, each offering its own unique view of the world. Here are your options:
This is the lens that enables you to shoot close-ups like a wasp or a flower head. A true macro offers 1:1 reproduction. That means the size you see it in real life is the size it will appear on the sensor. You can get macros that shoot at 1:2 but a true macro is always 1:1.
A true macro lens offers 1:1 reproduction, perfect for closeups.
A 50mm lens is considered a standard lens because back in 35mm film days people thought it equated to the angle of view that a normal person sees. Standard lenses now reach from 40mm to 70mm, and a standard zoom anywhere in the range of 24 to 70mm. They’re useful for all sorts of photography.
A wide-angle lens is generally used for interiors or architecture shots, where you can’t get back far enough to get everything into the frame. They range from 35mm down to 14mm and the smaller the value, the more your camera sees. Anything less than 17mm is considered to be ultra wide. When buying one of these it’s the corners of your shot you want to look at – you want low distortion and minimal falloff of sharpness.
Technically anything over 70mm is a telephoto and this is the way to go if you want to shoot wildlife. Telephoto lenses are also used in portrait photography. You pay more for a longer focal length but don’t let focal length alone dictate your options – it’s also worth looking out for image stabilisation and a faster lens (more on that in a bit).
All the other types of lenses we’ve talked about so far are known as rectilinear lenses. That means they keep straight lines straight. But there’s another type of lens, known as a circular lens or fisheye lens. Here, straight lines become curved as the photo is seemingly stretched around a bubble in the centre of the shot. Although often associated with comedy photos, they are also used to shoot architecture and sometimes even people, prized for their wide field of view because they can see almost 180-degrees. This shot by Photo by Urban Jyden on Unsplash shows the effect. The focal length ranges from 12mm down to about 6mm. At 8mm the image closes in on itself and shows as a circle.
Tilt Shift Lens
These are high-end, specialised lenses which bend light so it strikes the sensor at a different angle. Tilt Shift lenses are used a lot in architecture because they correct distortion effects but they can also create those model village-type, miniature shots where the periphery appears out of focus but the centre is perfectly crisp
When choosing your focal length you need to know which type of sensor your camera uses – either a full-frame or crop sensor. Nikon uses two sensor sizes in its range – full frame (FX) and 1.5x (DX) while Canon uses three sensor sizes – full frame (APS-S), 1.6x (APS-C) and 1.3x (1D). The sensor size affects the camera’s field of view so the ratio of the crop to the frame size directly impacts the focal length. It means that a lens with a 10mm focal length on a crop sensor is equivalent to a lens with a 15mm focal length on a full-frame camera. For macro photography that can be a bonus.
Aperture is a consideration, too. With an aperture of, say f/4, your shutter has to stay open for much longer than if you were using an f/2.8, or even an f/1.8. If you’re shooting something moving then this can make a massive difference, which is why aperture (ie speed) is so important for sports and wildlife photographers. That low f/stop value is helpful in other ways, too. Portrait photographers and wildlife photographers alike love how the low f/stop and wider aperture creates creamy backgrounds that make their subject stand out.
Fixed vs Prime
Lenses come with either a fixed focal length (known as prime lenses) or a variable focal range (say, 24mm-35mm, known as zoom lenses). You might wonder why you’d bother buying a fixed focal length lens when you can get more range with a zoom lens but a lens is a complex arrangement of special glass, bending light this way and that to make it hit the sensor in the best way. With a prime lens the optics don’t have to be so complex so as well as being less expensive and physically lighter, a prime lens will give you a noticeably sharper images, and likely be faster, too.
So before choosing, weigh up how much you need the ability to zoom in and out. In the early days of street photography when zoom lenses didn’t exist, the photographer would simply walk closer or further away from the scene to get the zoom they wanted. This might not work for architecture or landscape shots but if you’re shooting weddings or portraits then a prime lens is perfect.
One last thought: Give some thought to the future. Because while it’s ok to use a full frame lens on a crop camera, your image will be cropped if you try using a cropped lens on a full-frame camera. If you think you might upgrade to full-frame in the future, it pays to buy full-frame lenses if you can afford it. Whichever lens you go for, make sure it’s the right one for the job.