The lens is easily one of the most important element of a digital camera. It receives and focuses the light from your scene onto the image sensor, and if the lens quality is poor, then you are already starting out with a poor quality image.
camera-lens tipsIf you’re using a digital SLR camera (DSLR), the camera lens is interchangeable, i.e. you can remove the one currently attached and attach a new one. You can thus purchase the lens that suits the type of photography you’re most interested in doing: macro lens for close ups, wide-angle lens for landscapes, telephoto lens for sports, etc. When we are talking about non-DSLR cameras, the lens is permanently attached to the camera, and we say that the lens is “fixed.” It is, in most instances, a zoom lens with macro capability. In other words, manufacturers try to provide you a versatile lens that can take pictures in many situations: close ups, wide-angle, telephoto, etc. Its image quality is often not as good as a dedicated interchangeable lens.
When you look at the numbers given for a lens, it can get confusing, but it’s quite simple really. Typically, you’ll read something like this:
f=25-250mm 1:2.8-5.3
The “f=25-250mm” part says that the lens has a starting focal length of 25mm and ending focal length of 250mm. If we divide 250 by 25, we get 10, so it’s a 10x zoom lens. Note that a f=35-350mm is also a 10x zoom lens. So, when you hear about zoom power, you also need to know the starting and ending focal lengths to get a better idea of what the lens is capable of.
We generally call a lens with a focal length of around 50mm a standard lens. This is because the angle of view of the lens approximates our own eyes’ angle of view. So the lens “sees” what our eyes see. In fact, some photographers even call a 35mm a “standard” lens since we do have peripheral vision and do move our head left and right a bit even when we’re just looking straight ahead.
Anything less than 50mm is known as wide-angle: e.g. 35mm, 25mm, etc. At 25mm and less, we further qualify the lens as “ultra” wide-angle. And when the angle of view approaches 180° we call the lens a “fish-eye” since [some] fishes apparently can see 180 degrees all around. The wider the angle of view, the more scene you can capture: your group shots can contain more friends and family members without you having to back all the way to Katmandu to include everyone in, and your landscape shots approximate what we typically see when we move our heads left and right looking at a scene.
Any focal length greater than 50mm is known as a telephoto (or simply tele, for short). Lenses with focal lengths of 75mm, 100mm, 135mm, 200mm are known as medium tele, whereas those at 300mm and above are generally referred to as long tele lenses. The longer the focal length, the narrower the angle of view, and therefore the closer you can get to a far away subject, without having to walk close to it. Telescopes are basically long tele lenses.camera-lens-icon
If we build a lens where we can change its focal length by moving one or more lens elements inside, we end up with a zoom lens. Sports photographers who take pictures far from the action need a tele lens, so they typically buy a tele zoom lens, say with focal lengths ranging from 100mm to 300mm (a 3x zoom lens). This allows them to cover action that occurs far away (using 300mm) as well as closer (using 100mm), and anything in between. Typically, on fixed lens cameras, a good zoom lens should have a focal length range that covers a satisfying wide-angle (say, 25mm) to a medium tele (say 125mm). Dividing 125 by 25, we get a 5x zoom lens, but as you can see the zoom power itself is not as important as knowing the starting and ending focal lengths. This allows us to take large group shots and wide landscapes as well as nice portraits (without getting in our subject’s face). If you want an even more versatile zoom lens, our previous example of a 10x 25-250mm zoom lens would cover wide-angle to long tele.
There are some fixed lens cameras that also have a fixed focal length lens. The first “fixed” refers to the fact that the lens is not interchangeable; the second “fixed” refers to the fact that the lens is not a zoom lens, i.e. it has only one focal length, usually a wide-angle or standard focal length lens.
The “1:2.8-5.3? part says that the lens has a maximum aperture of f/2.8 at max. wide-angle and f/5.3 at max. tele. As we’ve already explained above, the wider the aperture, the better the light gathering ability of the lens.
You would usually not be concerned with the diameter of the lens. The diameter is what it is, and it’s not something you have much of a choice about. You need to be aware of it if the lens is threaded and allows you to screw a filter on. The diameter tells you the diameter of the filter you should purchase.
camera-lens tipsIf you’re using a digital SLR camera (DSLR), the camera lens is interchangeable, i.e. you can remove the one currently attached and attach a new one. You can thus purchase the lens that suits the type of photography you’re most interested in doing: macro lens for close ups, wide-angle lens for landscapes, telephoto lens for sports, etc. When we are talking about non-DSLR cameras, the lens is permanently attached to the camera, and we say that the lens is “fixed.” It is, in most instances, a zoom lens with macro capability. In other words, manufacturers try to provide you a versatile lens that can take pictures in many situations: close ups, wide-angle, telephoto, etc. Its image quality is often not as good as a dedicated interchangeable lens.
When you look at the numbers given for a lens, it can get confusing, but it’s quite simple really. Typically, you’ll read something like this:
f=25-250mm 1:2.8-5.3
The “f=25-250mm” part says that the lens has a starting focal length of 25mm and ending focal length of 250mm. If we divide 250 by 25, we get 10, so it’s a 10x zoom lens. Note that a f=35-350mm is also a 10x zoom lens. So, when you hear about zoom power, you also need to know the starting and ending focal lengths to get a better idea of what the lens is capable of.
We generally call a lens with a focal length of around 50mm a standard lens. This is because the angle of view of the lens approximates our own eyes’ angle of view. So the lens “sees” what our eyes see. In fact, some photographers even call a 35mm a “standard” lens since we do have peripheral vision and do move our head left and right a bit even when we’re just looking straight ahead.
Anything less than 50mm is known as wide-angle: e.g. 35mm, 25mm, etc. At 25mm and less, we further qualify the lens as “ultra” wide-angle. And when the angle of view approaches 180° we call the lens a “fish-eye” since [some] fishes apparently can see 180 degrees all around. The wider the angle of view, the more scene you can capture: your group shots can contain more friends and family members without you having to back all the way to Katmandu to include everyone in, and your landscape shots approximate what we typically see when we move our heads left and right looking at a scene.
Any focal length greater than 50mm is known as a telephoto (or simply tele, for short). Lenses with focal lengths of 75mm, 100mm, 135mm, 200mm are known as medium tele, whereas those at 300mm and above are generally referred to as long tele lenses. The longer the focal length, the narrower the angle of view, and therefore the closer you can get to a far away subject, without having to walk close to it. Telescopes are basically long tele lenses.camera-lens-icon
If we build a lens where we can change its focal length by moving one or more lens elements inside, we end up with a zoom lens. Sports photographers who take pictures far from the action need a tele lens, so they typically buy a tele zoom lens, say with focal lengths ranging from 100mm to 300mm (a 3x zoom lens). This allows them to cover action that occurs far away (using 300mm) as well as closer (using 100mm), and anything in between. Typically, on fixed lens cameras, a good zoom lens should have a focal length range that covers a satisfying wide-angle (say, 25mm) to a medium tele (say 125mm). Dividing 125 by 25, we get a 5x zoom lens, but as you can see the zoom power itself is not as important as knowing the starting and ending focal lengths. This allows us to take large group shots and wide landscapes as well as nice portraits (without getting in our subject’s face). If you want an even more versatile zoom lens, our previous example of a 10x 25-250mm zoom lens would cover wide-angle to long tele.
There are some fixed lens cameras that also have a fixed focal length lens. The first “fixed” refers to the fact that the lens is not interchangeable; the second “fixed” refers to the fact that the lens is not a zoom lens, i.e. it has only one focal length, usually a wide-angle or standard focal length lens.
The “1:2.8-5.3? part says that the lens has a maximum aperture of f/2.8 at max. wide-angle and f/5.3 at max. tele. As we’ve already explained above, the wider the aperture, the better the light gathering ability of the lens.
You would usually not be concerned with the diameter of the lens. The diameter is what it is, and it’s not something you have much of a choice about. You need to be aware of it if the lens is threaded and allows you to screw a filter on. The diameter tells you the diameter of the filter you should purchase.
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