Purchasing a DSLR or Digital Single Lens Reflex camera comes with a basic kit lens that could give decent quality pictures. But the advantage in DSLR cameras is being able to switch lenses, depending on the type of shot you want. There are powerful zoom lenses or macro lenses, for example.

Here are some factors to consider when buying a digital camera lens:

The Glass

• Focal Length – It is the actual distance in-between the focal lane of the lens and the rear element, measured in millimeters (mm). This is where the light's parallel beams enter the lens converging onto a point. It determines the viewing angle of the lens. When there is a shorter focal length, the field of view becomes wider, providing more scenes for your camera to capture. When you increase the focal length, the actual field of view becomes narrower.

• Aperture – It is one of the mechanisms that control the actual “amount of light” passing through the lens towards the image sensors. It is also referred as “f-stops,” like f/2/8. The smaller the number, the larger the opening. This means more light enters the camera. Since it begins to collect additional light, a type of lens that allows you to open to a wider aperture also enables you to have a faster shutter speed. Such feature is essential in low lighting conditions to obtain sharp images, especially through a handheld camera.

• Image Stabilization – Slower shutter speed can result to blurry photos when cameras are handheld. Image stabilization counteracts the shaking, allowing one to shoot certain handheld shots amidst low lighting conditions. Canon's term for this is IS (Image Stabilization). Nikon use the term VR (Vibration Reduction).

Zoom lenses included in a variety of DSLR kits offer focal lengths ranging from 18 to 35mm. Depending on the cropping capability of the camera, it can reach up to 55mm. This means that you can go from only a moderate “wide-angle” view towards a so-called “slight telephoto.”

If you have plans of expanding your digital camera's features, here are some things you need to consider:

• Prime Lenses – These should possess a longer type of zoom lens or a lone focal length between 35mm up to 85mm. Prime lenses have a better glass on them.

If you get the “fixed-length lens”, there is a tendency that you will be required to move around when getting your shot. Of course, over a certain time, this will already help you make better compositions.

Prime lenses also possess a wider type of maximum aperture, making it easier to get sharper shots, especially under low lightings.

• Zoom Lenses – For those wishing to get action photos, the best would be the “telephoto lens” which ranges from 100mm up to 300mm. This is due to the DSLRs crop factor. There is not much zooming needed. A good example would be Nikon D40 which has a 200mm type of telephoto lens that can turn into a 300mm one.