WHICH CAMERA LENSES SHOULD I BUY?

FACTORS TO CONSIDER


FOCAL LENGTH

Focal length is expressed in mm and a higher number means a bigger zoom, while a lower number mean the lens can be used for wider shots. As a rough reference, the human eye is said to see about the equivalent of 30-50 mm on a full frame camera (more on that later). A number lower than 30-50 mm will take in a bigger view than you naturally see, while higher numbers mean focus will be on a smaller aspect of your view.

MAXIMUM APERTURE

Maximum Aperture is shown in a number of ways, it all means the same thing and refers to the the maximum amount of light which the lens can gather. Lenses with larger maximum apertures (slightly confusingly these are the ones with lower numbers) are capable of gathering more light.

LENS MOUNT

It goes without saying that you want to buy a lens that will attach on your camera, and this is known as the lens mount. Camera manufacturers generally make lenses with proprietry mounts which will only fit their devices, sometimes having multiple lens mounts for different camera lines. The major exception to this is Micro Four Thirds lenses which can be used on respective Olympus and Panasonic cameras. Third party manufacturers also make lenses with mounts to fit various brands.

FORMAT

In addition to being able to mount the lens on your camera, you need to be sure it will produce an image big enough to cover the image sensor. Because different cameras use with different size of sensor manufacturers produce specific lenses to work with them.