A new digital camera comes with a multitude of features, but one of the first things we consider is the quality and power of the lens. But how many of us really understand what can be acheived by creative use of lenses?
The difference between a wide angle lens and a telephoto lens is about more than just magnification. To get the most out of your lenses, you also need to understand how they affect depth of field and perspective.
You already know that the telephoto lens enlarges everything in the picture. But did you also know that when you zoom in, or attach your large telephoto lens, you also reduce the depth of field around the subject? This is a great method for eliminating a distracting background from your photo. The result is twofold: the narrow field of view minimizes how much of the background we can see, and the small depth of field ensures it will be completely out of focus.
So when photographing subjects like people and animals, using your telephoto lens (or zooming in with your zoom lens) is often the best approach. The result will be a very three dimensional effect, with the subject appearing to emerge sharp and clear from the blurry background.
On the other hand, your wide-angle lens does just the opposite. It certainly does a lot more than just make everything appear smaller. The wide angle lens takes in (as the name suggests) a much wider angle of view, and it has a much stronger depth of field than a standard or telephoto lens. That means that not only will you see a lot more of the background in your photo, but it will also be much more focused.
Consequently the wide-angle lens is not so good for portrait style photos, because the background is too distracting. On the other hand, it is excellent for landscape pictures, especially when you have objects both in the foreground and background that you need to keep in focus.
The other aspect of your choice of lens is perspective, which is a lot harder to explain without pictures, but I will give it a go.
Have you ever watched a cricket match on television? (If you are from the United States substitute baseball here). When you see a close-up image of the batsman, you may notice that the wicket keeper (shortstop) seems to be standing right behind him, and the crowd is only a short distance further back. When you see a side-on view, you may be surprised to see that the wicket-keeper is standing about ten meters behind the batsman, and of course we know that the grandstand is a good 60 meters or so further back. So what's going on?
The answer is simple. The very large telephoto lens used for the close-up shot tends to make objects at different distances seem much closer to each other than they really are. In short, it compresses the natural perspective, making people separated by some distance appear to be quite close to each other.
This principle also applies to landscape photography. Imagine a scene with a tree in the foreground and a mountain range in the distance. By standing a long way from the tree and shooting it with a telephoto lens, you will also enlarge the mountains in the background. As a result, they will appear much closer to the tree than they really are.
Now imagine taking the same scene with a wide-angle lens. By standing a lot closer to the tree, you can photograph it in such a way that it takes up the same amount of space in the composition. However, by reducing the scene to fit the tree in the frame, you also reduce the background. . . making it appear much further away than it really is.
In this way, the wide-angle lens does the opposite of the telephoto lens. It exaggerates the perspective, making objects at different distances appear much further apart than they really are.
Put simply, the end result of these two approaches is this; the telephoto lens adds prominence to the background, which will appear relatively large in your photos (albeit with depth of field issues in some cases). The wide-angle lens adds prominence to the foreground, making the background appear much smaller and more distant.
Thus by simply changing your choice of lenses, you can dramatically alter the impact of your photos. Imagine the creative possibilities; you have the power to control how the viewer sees not only your subject, but how it relates to the surroundings at the same time.
This is a tough subject to explain without pictures, but hey - you have a digital camera. Why not step outside right now and try out a few of these ideas. Or if you are feeling lazy, sit down and watch some sport on telly. It may actually teach you something about photography.
Andrew Goodall is a professional nature photographer of 20 years experience. He is also an author, teacher and gallery owner. Visit http://www.naturesimage.com. au where you can see Andrew's images and ebooks, and subscribe to the free online newsletter for further tips.