Photography - Choosing the Right Lens

Slowly, but surely, the worth of the fixed focalcamera ends up in the image!
length lens (or prime lens) to the non-professionalThe second consequence is that cramming more
photographer is being eroded by the increasingof the scene into the image distorts the image to
perfection of zoom lens technology. The dayssome degree. Straight lines in the real world, like
when you packed your camera bag with trustythe horizon and the edges of walls, become
28mm, 50mm, 85mm, 105mm, and even 180mmcurved. Most of the time this is acceptable,
lenses are rapidly disappearing. Why bother whenbecause capturing the entire scene is the most
you can simply reach for something like Nikon'simportant consideration.
all-purpose Nikkor 18-200mm DX VR zoom lensUsing a wide angle prime like the 28mm becomes
and know that you have both flexibility and opticalnecessary when you try to capture images in
speed at your fingertips?confined spaces. To shoot all of the board
The truth is that, while the range of focal lengthsmembers in the annual meeting while they sit at
may be increasing within a single zoom lens, nothe conference table, and to get all of the table
all-purpose lens is ever likely to perform at theplus the room around it into focus, requires a wide
level of eqivalent prime lenses for its full range ofangle lens. The other situation that calls for a wide
focal lengths.angle arises when you find yourself trying to
Zooms are engineered with a good deal morephotograph a very large object that won't quite
glass than is found in a prime lens, and because offit into the frame. If you were taking a picture of
this they "swallow" more light than thesomeone standing at the base of the Eiffel
corresponding lens of the same focal length.Tower, using a wide angle will help you fill the
Unless you are photographing under very brightframe with both the subject and the tower.
light, the required increased shutter duration time85mm to 105mm
of a zoom may make the difference between aI have mentioned how useful the 50mm prime
good image, and one that is ruined by cameralens is for doing portraiture. However, the lens
lens wobble.most often mentioned in connection with portrait
Even so, there is a lot to be said for carrying oneshots is the 85mm prime, usually with an f/1.8
lens, and leaving it attached to your camera,maximum aperture, or the even faster f/1.2
rather than carrying five separate lenses andThe 85mm is sometimes referred to as a short
having to miss photo opportunities that arise whiletelephoto. Unless your aim is to capture just the
you are changing lenses.upper torso of your subject, or simply their face
But thinking about fixed focal length lenses can bewhen closer in, you will need to back off to
instructive. When we plunge into photography withcapture your subject from head to foot. This
a zoom lens, the effortless continuum of focalmeans that you can often take unobtrusive and
lengths is apt to blur the distinction betweenspontaneous portrait shots simply by being in the
photographs captured at different focal lengths.vicinity of your subject as they go about their
Historically this just wasn't a problem. Economyactivities.
demanded that the lenses you purchased wereBut the real strength of the 85mm, or even the
quite distinct, focal length wise, and so an105mm, prime, lies with the ability of the lens to
appreciation of their individual characteristics cameget in tight and emphasize the features of the
easy.subject's face. The background in these shots is
50mmnot the least important, and by opening up to the
It used to be the case that the kit lens for amaximum aperture you will be able to throw the
35mm SLR was generally a 50mm focal lengthbackground completely out of focus. Focusing
lens. The 50mm lens reproduces a field of viewbecomes critical in this situation, so concentrate on
that approximates normal vision, with an angle ofthe subject's eyes which can never be unsharp in
coverage of around 50 degrees. But this is alsoacceptable portraiture shots.
partly the reason that the 50mm lens gets only a180mm
fraction of the respect it deserves. Because whenThere will always be times when you cannot get
we look at the scene captured by a 50mmclose to the scene that you want to photograph.
image, we are not going to see something thatThis is where telephoto lenses come in handy.
we could not have seen with our own eyes. ThisMedium telephoto range like that provided by the
means there are no optical effects to draw us180mm prime is useful for photographing local
into the image, so the subject material must besports events, where you can approach the edge
strong enough to command our attention.of the field.
Despite the fact that the 50mm kit lens has beenPrime telephotos capture only a small portion of
replaced with an optical zoom lens (usually in thethe scene before you, so in order to pull in
range of 28-80mm these days) the 50mm lensenough light that you can see the scene properly,
has a lot going for it. For one thing it's generallythe size of the lens has to grow. In other words,
very fast. My 50mm kit lens (picked up decadesyour 180mm lens is going to weigh you down a
ago) is an f/1.4 Nikkor. By dialing up to the largestlittle. For this reason, even if you are
aperture you can get away with not using a flashphotographing at maximum aperture, it is a good
when taking indoor photographs in natural lighting.idea to use a monopod to steady your shot. Hand
This means that your shots will look more natural,holding a telephoto quickly becomes not only a
and have a depth to them that washed-outchore, but a great way to lessen the likelihood of
images captured with flash simply cannot match.a sharp image. This is where the addition of
You'll also be able to shoot fast. The equivalentvibration reduction technology to the lens (or
focal length on a zoom might be two, or evenimage stabilization, as it is also known), can be
three, stops slower.very advantageous (but extremely costly for
If you will be using your camera mostly to recordtelephotos).
family shots, and you will be shooting indoors aLike the short telephotos discussed already,
good fraction of the time, you might want tofocusing becomes even more critical here. Unless
take a serious look at picking up a 50mm f/1.8, oryour subject remains relatively still, or your lens is
even an f/1.4 if you have the money to spend.capable of rapid auto focusing, some real amount
To read a fine essay on the under-appreciation ofof practice is required before you can consistently
the 50mm lens, I recommend The Forgottenshoot great action shots with a telephoto. On the
Lens by Gary Voth.other hand, the results are worth it.
28mmSo to wrap up, I have summarized the
Open up a book on photojournalism and you'llcharacteristics and uses of several different focal
discover a slew of images captured with widelength lenses. Try to keep these characteristics in
angle lenses like the 28mm prime lens. Wide anglemind if you are shooting with a zoom that covers
prime lenses have a remarkable pronouncedsome, or all, of the focal lengths discussed here. If
curvature on the front lens element which helpsyou think about your shots in terms of these
to pull in light from all around the edges of adifferent focal length characteristics you'll be
scene. This has two main consequences.better able to harness them to improve your
The first is that a much larger portion of thephotography.
scene before you is captured. Extremely shortTo help you select a suitable digital camera to get
focal length primes, like the 8mm, are known asstarted with, I have put together an article for
fisheye lenses because the angle of coverageyou about how to find the right Beginner Digital
exceeds 180 degrees. Everything in front of theCamera.