Camera Lens Types-Zoom Lenses and Fixed Focal Length Prime Lenses
Lens types can generally be put into two categories, Fixed Focal Length lenses and Zoom lenses. Fixed Focal
length lenses are also known as Prime lenses.
Macro lenses, which are used for extreme close up photography will also be included in this tutorial. Macro
lenses can be in either the zoom lens or prime lens category.
The main difference between the lens types is that Fixed Focal length/ Prime lenses have a pre-set focal length
that cannot be changed whereas a zoom lens can be used at various focal lengths. There are also differences
in the size, weight, price, and optical quality of zoom lenses compared to prime lenses.
Camera Lens Focal Lengths:
The focal length of the lens will determine how near or far away the image of a subject or scene will appear in
the camera's viewfinder or LCD screen. Focal lengths are written in terms of millimeters such as a 50mm lens or
a 200mm lens for fixed focal length lenses.
Since zoom lenses can be used at different focal lengths, their focal lengths are expressed as a range, such as
a 28mm to 105mm lens or a 10mm to 28mm lens.
A picture taken with a 28mm lens will give a wide view of a scene and that scene will appear more distant than if
taken with a 135mm lens. A picture of the same scene taken from the same distance with a 135mm lens instead
of a 28mm lens will produce a closer, more magnified view. Also, less of the scene will be shown in the camera's
viewfinder or LCD screen.
The focal length of a lens is written right on the barrel of the lens for easy identification. Some of the common
fixed focal lengths and zoom focal lengths are listed below.
Fixed Focal Lengths: 24mm 28mm 35mm 50mm 55mm 85mm 105mm 135mm 200mm 300mm 400mm
Zoom Focal Length Ranges: 10-22mm 18-105mm 28-135mm 18-200mm 55-200mm 75-300mm
As you can see, both fixed focal length and zoom lenses are manufactured in a wide variety of focal lengths from
wide angle to telephoto.
The lens maximum aperture must also be considered when discussing lenses. The lens aperture size will affect
the lens ability to take pictures in low light situations as well as the Depth of Field. (how much of the picture will
be in or out of focus.) Please read our Camera Aperture and Depth of Field tutorials if you are not familiar with
F/stops, Depth of Field, and how the camera aperture works.
Zoom lenses: .
The best feature of a zoom lens is its flexibility. One zoom lens can do the job of several different fixed focal
length lenses. Zoom lenses enable you to photograph a subject at varying focal lengths without having to
change your position or the camera lens. That simply means for example that if you are using a 24-120mm zoom
lens, you can shoot a scene using the 24mm focal length and then shoot the same scene using the 135mm
focal length or any focal length in between with the same lens.
Zoom lenses are extremely popular these days and many Digital SLR camera manufacturers like Canon and
Nikon include a zoom lens as part of some of their camera kits instead of a fixed focal length lens
Some typical examples of zoom lenses and their range might be a Canon 75-300mm, F/4.0-5.6 lens or a
Tamron 10-24mm, F/3.5-5.6 lens. The lens in the first example can be used at focal lengths from 75mm all the
way up to 300mm. The maximum aperture opening that can be used when the focal length is set to 75mm is
F/4.0. The maximum aperture opening that can be used when the focal length is set to 300mm is F/5.6. These
are known as variable aperture zoom lenses.
The changing maximum aperture is probably not be much of a problem for the average photographer. However,
there are constant aperture zoom lenses available that will stay at the same aperture setting no matter what
focal length is being used. Some examples of those type of lenses are the Nikon 24-120mm, F4 lens or the
Canon EF 70-200mm F4 lens. However, those type lenses will cost a lot more than your average zoom lens.
The maximum aperture opening on your average zoom lens usually will not be as large as the maximum aperture
on a prime lens at an equal focal length. Therefore, many zoom lenses can be less effective in low light
situations. However, there are "fast" zoom lenses available. A "fast "zoom lens will have a maximum aperture
such as F/2.8 which will allow more light into the lens than a F/4.0 lens and will enable you to use faster shutter
speeds in low light situations. The Nikon AF-S Nikkor 80-200mm F2.8 lens is a good example of a "fast" zoom
lens.
Zoom lenses are more expensive, a little bulkier, and the optical quality of some zoom lenses might not be as
sharp as a prime lens. The reason for a slight difference in sharpness is because of the additional lens elements
and moving parts required to manufacture a zoom lens.
Overall, due to the great technology advances of recent years, the performance of most "quality" zoom lenses is
pretty close to the performance of the prime lenses.
Fixed Focal Length/Prime Lenses
The three main types of prime or fixed focal length lenses are Standard, Wide Angle, and Telephoto lenses.
The standard lens for a Single Lens Reflex camera is a 50mm or 55mm focal length. That focal length most
closely duplicates the viewing area that humans see with their own eyes. A standard or "normal" lens like the
Canon EF 50mm F1.8 is usually very sharp, inexpensive and light.
Standard lenses will likely have larger maximum aperture openings than most zoom lenses. The larger maximum
aperture allows more light into the lens for low light picture taking situations which also allows faster shutter
speeds to be used. If you are not sure how the camera shutter and aperture work together to produce properly
exposed pictures, check the Exposure Basics tutorial for more information.
Before zoom lenses became so popular, just about every 35mm camera came equipped with a 50mm standard
lens. The optical quality of these lenses is usually excellent. The only drawback is that you have to do more
moving around to frame an image in the camera's view finder or LCD screen than if you were using a zoom lens.
But that is not necessarily a bad thing, especially for those who are learning or practicing better picture
composition.
Just about every professional photographer will have a standard lens included in their collection of lenses. That
fact speaks volumes about the quality and usefulness of the standard lens.
Telephoto lenses magnify and bring everything in the viewfinder or LCD screen closer. Long focal length
lenses between 70mm and 300mm or more are called telephoto lenses.
Lenses like the Sigma Telephoto 180mm F3.5 are ideal for situations where you cannot, or perhaps do not want
to get too close to the subject. A typical example might be photographing an animal in the wild when it might be
too dangerous to get close
A telephoto lens might also be used in landscape photography when you might want to
get a closer view of a portion of a very wide area.
Medium telephoto lenses with focal lengths between 80mm and 130mm are excellent
for portraits. That is because there can be a little more distance between the photographer and the subject,
making the subject feel less self-conscious.
Long focal length lenses like a 600mm telephoto lens are heavier, larger, and less convenient to carry around.
Also, their maximum aperture openings tend to be not as wide as the standard or wide angle lenses. Please
note that, same as with zoom lenses, there are telephoto lenses that have large maximum aperture openings ,
but they are a more expensive.
Wide angle lenses cover a wider area than the normal views of the human eye. Most lenses under 50mm focal
length are considered to be wide angle lenses. Wide angle lenses are very sharp, small and lightweight.
Wide angle lenses are great for landscapes and large groups. They are also good for photographing buildings
and interiors.
Macro lenses are lenses for very close up photography. A macro lens has smaller minimum focusing distance
than a normal camera lens. A regular camera lens cannot focus on a small subject like an insect unless you are
almost a couple of feet away. And even then the subject will just be a little speck in the picture. Macro lenses
similar to the Canon EF-S 60mm F2.8 Macro lens allow you to get within inches rather than feet to focus and
the subject will appear much larger in the picture.
Although a Macro lens is a specialty type lens, many zoom lenses
like the Canon AF 70-300mm F4-5.6 lens as well as compact digital
camera lenses have the Macro capability.
Some of the more common fixed focal lengths for macro lenses are
listed below. In general, the longer focal length macro lenses will cost
more than the ones with shorter focal lengths.
50mm 55mm 60mm 65mm 100mm 105mm 180mm
Also, it is important to know that the depth of field can be very shallow
when using a macro lens. So you will want to keep as much of the
image as possible on the same focusing plane That will help to keep
more of the subject in sharp focus. That is, unless you intentionally
want one area sharp and other areas of the image blurred.
Although the specialty of macro lenses is close up photography, they
can also be used for everyday photography as well. In other words,
you can take a close up picture of a beautiful flower in a garden and
then turn around and take a portrait of someone without having to
change the lens.
Lens types can generally be put into two categories, Fixed Focal Length lenses and Zoom lenses. Fixed Focal
length lenses are also known as Prime lenses.
Macro lenses, which are used for extreme close up photography will also be included in this tutorial. Macro
lenses can be in either the zoom lens or prime lens category.
The main difference between the lens types is that Fixed Focal length/ Prime lenses have a pre-set focal length
that cannot be changed whereas a zoom lens can be used at various focal lengths. There are also differences
in the size, weight, price, and optical quality of zoom lenses compared to prime lenses.
Camera Lens Focal Lengths:
The focal length of the lens will determine how near or far away the image of a subject or scene will appear in
the camera's viewfinder or LCD screen. Focal lengths are written in terms of millimeters such as a 50mm lens or
a 200mm lens for fixed focal length lenses.
Since zoom lenses can be used at different focal lengths, their focal lengths are expressed as a range, such as
a 28mm to 105mm lens or a 10mm to 28mm lens.
A picture taken with a 28mm lens will give a wide view of a scene and that scene will appear more distant than if
taken with a 135mm lens. A picture of the same scene taken from the same distance with a 135mm lens instead
of a 28mm lens will produce a closer, more magnified view. Also, less of the scene will be shown in the camera's
viewfinder or LCD screen.
The focal length of a lens is written right on the barrel of the lens for easy identification. Some of the common
fixed focal lengths and zoom focal lengths are listed below.
Fixed Focal Lengths: 24mm 28mm 35mm 50mm 55mm 85mm 105mm 135mm 200mm 300mm 400mm
Zoom Focal Length Ranges: 10-22mm 18-105mm 28-135mm 18-200mm 55-200mm 75-300mm
As you can see, both fixed focal length and zoom lenses are manufactured in a wide variety of focal lengths from
wide angle to telephoto.
The lens maximum aperture must also be considered when discussing lenses. The lens aperture size will affect
the lens ability to take pictures in low light situations as well as the Depth of Field. (how much of the picture will
be in or out of focus.) Please read our Camera Aperture and Depth of Field tutorials if you are not familiar with
F/stops, Depth of Field, and how the camera aperture works.
Zoom lenses: .
The best feature of a zoom lens is its flexibility. One zoom lens can do the job of several different fixed focal
length lenses. Zoom lenses enable you to photograph a subject at varying focal lengths without having to
change your position or the camera lens. That simply means for example that if you are using a 24-120mm zoom
lens, you can shoot a scene using the 24mm focal length and then shoot the same scene using the 135mm
focal length or any focal length in between with the same lens.
Zoom lenses are extremely popular these days and many Digital SLR camera manufacturers like Canon and
Nikon include a zoom lens as part of some of their camera kits instead of a fixed focal length lens
Some typical examples of zoom lenses and their range might be a Canon 75-300mm, F/4.0-5.6 lens or a
Tamron 10-24mm, F/3.5-5.6 lens. The lens in the first example can be used at focal lengths from 75mm all the
way up to 300mm. The maximum aperture opening that can be used when the focal length is set to 75mm is
F/4.0. The maximum aperture opening that can be used when the focal length is set to 300mm is F/5.6. These
are known as variable aperture zoom lenses.
The changing maximum aperture is probably not be much of a problem for the average photographer. However,
there are constant aperture zoom lenses available that will stay at the same aperture setting no matter what
focal length is being used. Some examples of those type of lenses are the Nikon 24-120mm, F4 lens or the
Canon EF 70-200mm F4 lens. However, those type lenses will cost a lot more than your average zoom lens.
The maximum aperture opening on your average zoom lens usually will not be as large as the maximum aperture
on a prime lens at an equal focal length. Therefore, many zoom lenses can be less effective in low light
situations. However, there are "fast" zoom lenses available. A "fast "zoom lens will have a maximum aperture
such as F/2.8 which will allow more light into the lens than a F/4.0 lens and will enable you to use faster shutter
speeds in low light situations. The Nikon AF-S Nikkor 80-200mm F2.8 lens is a good example of a "fast" zoom
lens.
Zoom lenses are more expensive, a little bulkier, and the optical quality of some zoom lenses might not be as
sharp as a prime lens. The reason for a slight difference in sharpness is because of the additional lens elements
and moving parts required to manufacture a zoom lens.
Overall, due to the great technology advances of recent years, the performance of most "quality" zoom lenses is
pretty close to the performance of the prime lenses.
Fixed Focal Length/Prime Lenses
The three main types of prime or fixed focal length lenses are Standard, Wide Angle, and Telephoto lenses.
The standard lens for a Single Lens Reflex camera is a 50mm or 55mm focal length. That focal length most
closely duplicates the viewing area that humans see with their own eyes. A standard or "normal" lens like the
Canon EF 50mm F1.8 is usually very sharp, inexpensive and light.
Standard lenses will likely have larger maximum aperture openings than most zoom lenses. The larger maximum
aperture allows more light into the lens for low light picture taking situations which also allows faster shutter
speeds to be used. If you are not sure how the camera shutter and aperture work together to produce properly
exposed pictures, check the Exposure Basics tutorial for more information.
Before zoom lenses became so popular, just about every 35mm camera came equipped with a 50mm standard
lens. The optical quality of these lenses is usually excellent. The only drawback is that you have to do more
moving around to frame an image in the camera's view finder or LCD screen than if you were using a zoom lens.
But that is not necessarily a bad thing, especially for those who are learning or practicing better picture
composition.
Just about every professional photographer will have a standard lens included in their collection of lenses. That
fact speaks volumes about the quality and usefulness of the standard lens.
Telephoto lenses magnify and bring everything in the viewfinder or LCD screen closer. Long focal length
lenses between 70mm and 300mm or more are called telephoto lenses.
Lenses like the Sigma Telephoto 180mm F3.5 are ideal for situations where you cannot, or perhaps do not want
to get too close to the subject. A typical example might be photographing an animal in the wild when it might be
too dangerous to get close
A telephoto lens might also be used in landscape photography when you might want to
get a closer view of a portion of a very wide area.
Medium telephoto lenses with focal lengths between 80mm and 130mm are excellent
for portraits. That is because there can be a little more distance between the photographer and the subject,
making the subject feel less self-conscious.
Long focal length lenses like a 600mm telephoto lens are heavier, larger, and less convenient to carry around.
Also, their maximum aperture openings tend to be not as wide as the standard or wide angle lenses. Please
note that, same as with zoom lenses, there are telephoto lenses that have large maximum aperture openings ,
but they are a more expensive.
Wide angle lenses cover a wider area than the normal views of the human eye. Most lenses under 50mm focal
length are considered to be wide angle lenses. Wide angle lenses are very sharp, small and lightweight.
Wide angle lenses are great for landscapes and large groups. They are also good for photographing buildings
and interiors.
Macro lenses are lenses for very close up photography. A macro lens has smaller minimum focusing distance
than a normal camera lens. A regular camera lens cannot focus on a small subject like an insect unless you are
almost a couple of feet away. And even then the subject will just be a little speck in the picture. Macro lenses
similar to the Canon EF-S 60mm F2.8 Macro lens allow you to get within inches rather than feet to focus and
the subject will appear much larger in the picture.
Although a Macro lens is a specialty type lens, many zoom lenses
like the Canon AF 70-300mm F4-5.6 lens as well as compact digital
camera lenses have the Macro capability.
Some of the more common fixed focal lengths for macro lenses are
listed below. In general, the longer focal length macro lenses will cost
more than the ones with shorter focal lengths.
50mm 55mm 60mm 65mm 100mm 105mm 180mm
Also, it is important to know that the depth of field can be very shallow
when using a macro lens. So you will want to keep as much of the
image as possible on the same focusing plane That will help to keep
more of the subject in sharp focus. That is, unless you intentionally
want one area sharp and other areas of the image blurred.
Although the specialty of macro lenses is close up photography, they
can also be used for everyday photography as well. In other words,
you can take a close up picture of a beautiful flower in a garden and
then turn around and take a portrait of someone without having to
change the lens.
Easy Basic Photography
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