A good lens is a wonderful thing—and every bit as important as a good camera body. The huge number of megapixels available on modern DSLRs are wasted if images are captured through a soft, dull piece of glass. As you grow as a photographer you will learn to appreciate the quality—and in some cases the deficiencies—of different lenses.
But which lens to get started? Your choice depends on what you’d like to shoot and on your budget. In this tutorial I’ll try and point you toward options that will help you learn and develop your skills, but also look at which types of lens best suits which type of photography.
My first point may come as a shock; it certainly did to me when I started out. An SLR lens does not fit on any SLR camera. A Canon lens won’t work on a Nikon and an old film-era lenses won’t work on modern DSLRs, in many cases. Cameras have different mounts (put crudely, the size and shape of the hole to which a lens attaches) and nowadays there are all sorts of electronics that have to connect between camera and lens. So hold your horses before grabbing the ‘bargain’ lens you’ve spotted in the charity shop. First check that it will fit on/work with your camera body.
Many DSLRs offers include a lens, apparently ‘free’ or at a considerable saving. On the positive side, you gain a lens that has a general purpose zoom, meaning you can experiment with different focal lengths. Also, since they are cheap (although only ever ‘free’ in the same way as an airline meal is) you aren’t investing much. On the negative side, the image quality is poor. I would recommend spending a little more and aiming higher.
Most people are familiar with a zoom lens. It covers a range of focal lengths. My most-used lens is a ‘general purpose’ zoom 24mm–70mm. A 24mm (or anything below 35mm) lens is classed as wide-angle; 70mm and beyond is classed as telephoto.
Wide-angle is fairly self-explanatory—it encompasses a large portion of the view in front of you.
Telephoto is the opposite. Like a telescope, it allows you to see a much smaller portion but magnified or ‘brought closer’.
A prime lens has only one focal length, that is, it doesn’t zoom. It can be wide-angle, telephoto, or ‘normal’ (around 50mm which offers roughly the perspective of the human eye). What it lacks in the flexibility of a zoom it makes up for in sharpness and often in width of aperture, which allows for crisper shooting in low light conditions. A lens with a wide aperture is known as a ‘fast’ lens.
Different lenses suit different types of photography. A sports or a nature photographer might use a telephoto much of the time, often a huge bazooka of a lens with a focal length of 300mm or more. A photojournalist or candid street photographer might often opt for a wide-angle lens when s/he is in the midst of the action. A portrait photographer might want to stick to a ‘normal’ lens and possibly a prime lens in order to get a narrow depth of focus and therefore draw attention to the eyes. A landscape photographer would probably use a range of focal lengths and might be advised to invest in a general-purpose zoom.
That said, there are no hard and fast rules. Some of the best nature photography I’ve seen was shot on normal or wide-angle lenses. The unusual perspective and sense of closeness to a wild animal that the viewer gains is fresh and thrilling.
Many photographers, when they’re starting out, have only a vague idea of what they might shoot. You may love nature but soon come to realize that spending days on end waiting for a shot of a woodpecker is a little unrealistic. Instead you may point your camera toward your children.
In order to remain flexible, I would recommend starting off with a general-purpose zoom. Something in the region of 24–70mm or 28–105mm gives you lots of scope for experimentation. You may not be able to catch the expression on the batsman’s face when he is bowled out, but you can do plenty of portraits, landscapes and close-quarter action.
A 50mm prime lens is also great to have, not least for portraits. They tend to be small, wonderfully sharp, and fast. The benefits of sharpness and speed may not be immediately apparent but they will become more and more so as you progress. And 50mms are cheap—you should be able to pick one up for around $100.
And yes, you might want to throw in a telephoto zoom (something like a 70–300mm).
You may find lenses with similar focal lengths at very different prices. There are many factors that constitute quality, or lack thereof. Materials are one—they determine durability and image quality (beware plastic lenses).
But probably the biggest factor is the ‘F’ number. This refers to the width of aperture. A cheap zoom may be marked f/4.5–5.6. This means in low light (dusk, indoors) you would really struggle to get sharp shots. By contrast, one prime lens I love is f/1.4. This lets in 3 or 4 times as much light as the cheap zoom. This may sound arbitrary but it makes a world of difference if you’re shooting in a church without using flash.
It’s more expensive to produce lenses with wider apertures (smaller F number) and they are usually better quality all around.