Your images will only ever be as good as the glass you use, so don’t blow all your budget on an amazing camera body and end up with a cheap or kit lens. Professional photographers tend to upgrade their camera body every 2-5 years, but top quality lenses can last much, much longer, so consider them a long-term investment: cameras wear out, but lenses don’t.
Lenses that are included with entry-level and mid-range camera bodies tend to be lower quality, made from cheaper materials and with limited aperture ranges. Instead, get the very best you can afford, and you will reap the rewards with superior image quality.
Naturally, people want a single lens that can do everything, and for a low price, but as with most things, there are compromises to be made. Some of the things to consider before buying a lens include:
Focal length
The focal length of a lens refers to the magnification of a scene that it provides. Wide angle lenses, such as an 18mm or 24mm lens, enable you to fit more of a scene in and are best for group portraits. However, if you want to fill the frame with the face of a single subject, then you’d need to move in very close to him or her. Not only could this feel intimidating, it will also result in distorted portraits with exaggerated foreshortening, giving your subject a huge nose and tiny ears.
Telephoto lenses, such as an 85mm or 200mm lens, have a much narrower angle of view, and enable you to crop in close to one part of a scene or subject. However, you need to move further away from your subject in order to include more of their body in the shot. This can make it harder to interact, and can be impossible in a small room. Longer focal lengths can also flatten perspective, making the background look much closer to the subject than it really is – something that you can often use to your advantage, but need to be aware of. This lens type produces much more flattering shots than wide angle lenses, and can feel less intimidating as they are used further away from the subject.
Whether you choose a wide angle or a telephoto lens, bear in mind that unless you have a camera with a full frame sensor, the actual focal length will be more magnified, as smaller sensors ‘crop’ into the image. This means that a 50mm lens would have an effective focal length of 75mm-80mm on a camera with an APS-C sensor.
As a minimum, professional photographers would typically have a 24-70mm lens for wider angle work and a 70-200mm lens for close-up work. Wedding photographers may also have a 16-35mm, in order to include more of the venue in shots, and for group portraits, and possibly a ‘fast’ prime lens too.
Maximum aperture
Wide apertures enable you to isolate the subject by blurring the foreground and background. They also allow more light through…