Professional photographers generally have at least a couple of lenses in their bags that allow them to tailor their lens choices for specific situations or to create certain effects. While there is really no best lens to own, certain subjects or circumstances are easier to handle with specific lenses. Here's a look at some different situations and suggestions for the appropriate lens choices for each.

If you are out to photograph an eagle's nest in the wild, you will need to stay far away from your subject. A 200mm telephoto lens might work if you can get close enough. If not, you'll need an even longer telephoto lens, possibly 800mm or 1200mm.

If you're shooting a serene landscape scene, go for a wide-angle lens. A 20mm–35mm zoom will give you several composition options.

Before you take a portrait, decide whether the picture is about the person or the person within the context of her environment. In other words, do you want the person to be the emphasis, or do you want to show how the person relates to her surroundings?

For the person alone picture, use a telephoto lens (95mm–110mm) for head and shoulders and to keep the subject separated from the background. Shooting with a large aperture (f/1.4, f/2, f/2.8) will throw the background out of focus while keeping eyes (usually the most important part) in focus.

For the person in her surroundings picture, select the view you want of the scene and the lens that lets you fill the frame the way you would like. Then position the subject so that her size and pose tell the story (what dominates the scene — the subject, or the room?). Use the combination of lens choice, camera placement, and subject position to tell the story.

The photographer on the sidelines at a professional sporting event may need a 300mm lens, but if the amateur athlete you are documenting is more approachable, a better choice of lens might be one in the range 85mm–180mm. For sports photography from the sidelines, 200mm–300mm is good.

To photograph interior architecture, select a wide-angle lens with a focal length of 24mm — or even 17mm, which is a super-wide angle. If most of your pictures will be taken inside your home or in a small backyard, you'll be happier with lenses in the wide-angle category.

Photographing stage shows — or any other dimly lit event at a distance — requires a lens that lets in a lot of light and that has a focal length of 100mm–200mm.

As a general rule, when photographing a group of people who are in several rows parallel to the film plane, a longer lens will produce a more honest picture. The wide-angle lens allows the camera to be closer to the group in order to fill the frame. The people closest to the camera are significantly closer than the people in the back row, so the front row people appear larger. Back away from the group and switch or zoom to a longer focal length. The farther away you get, the more the people in the front row will be in scale with the ones in the back row. Even if you don't switch lenses, the more accurate scale provided by greater distance will still be apparent. The reason you switch lenses is to keep the frame filled with the people, rather than unimportant surrounding scenery.