The flexibility of being able to use a variety of camera lens is one of the key features of a digital SLR camera. The camera is only part of the picture that you take. The lens itself is very important in how every photo looks that you take. If you are taking a lot of sports action photos, you will want one type of lens. If you are taking a great deal of wildlife or nature pictures, you would probably want another type.

You can purchase two basic types of lens:

• Prime: These lenses have fixed focal lengths, are fast and bright, and are extremely high quality. They are designed for only 1 focal length.
• Zoom: These allow you to choose from many focal lengths, making this lens more versatile. However, zoom lenses are not as fast, and there are more aberrations in their photos than with prime lenses.

Many SLRs now come with a standard zoom camera lens that ranges from 35-70mm, or 28-55mm.

In prime lenses, the basic ones are:

• Standard (50 mm): This is the lens that will come with most SLRs. This is a lens for general picture shooting, and gives you a view that is similar to that of the human eye. These are compact and lightweight, and provide nice, sharp images.
• Wide Angle: (less than 50mm): People who shoot landscapes, wildlife and outdoors usually select a wide angle lens. One of these lenses gives you a depth of field that is very deep, so you do not need to adjust your focus all the time.
• Medium Telephoto (85-135mm): This is the lens of choice for a portrait. This one will isolate the subject of your picture more from the surroundings. The greater focal length also will flatten the image somewhat.
• Long Telephoto (more than 135mm): This is what you use for sports shots, or other types of shots where you have to have an up close image but you cannot actually be physically up close.

If you want a zoom camera lens, consider one of these:

The Canon EF-S 18-55mm f/3.5-5.6 IS II is a starter lens and does not do everything well. However it is quite a good value if purchased with an SLR camera. It is often the lens paired with many entry level SLRs.  It is inexpensive, small and very light. It has pretty good image stabilization and has a good focal length range for general purposes. This camera lens will function fairly well in a low light setting, as long as the subjects are not in motion. This lens is fairly slow, meaning that the aperture is narrow.

The Canon EF-S 17-55mm F/2.8 IS USM has a fixed, fast aperture of f/2.8, extremely superior image quality, as well as image stabilization with three stops. This is one of the best general purposes lenses on the market. This lens has many great features, very high image quality and is the choice of many amateur and professional photographers.