Camera lens: Different types of camera lenses
To new photographers it can be quite surprising just how many types of lenses there are. Some manufactures offer dozens of lenses at any given time. Understanding the options is the first step to building your own photo system.
Basic Lens Types
At a glance there are three basic types of lenses: wide, normal and telephoto. All lenses, in some way, warp what they are looking at. The way they focus light can make the foreground and background appear really close together or really far apart. A normal lens is one where these layers appear most like they do to the human eye. Ones that push the background away are wide. Those that bring the background close are telephoto. The more popular lenses are called zoom lenses. These are extendable lenses that are often (but not always) wide, normal and telephoto all built into one.
Stabilization
For someone who likes to photograph sports, wildlife and other things that are typically far away, a telephoto lens is essential. A big telephoto lens can magnify its subject 2 to 20 times (and then some…), with telephoto zooms giving you options within a given range.
The problem a lot of photographers faced over the years is that these lenses can get quite big, heavy and hard to hold; this makes it hard to hold a lens steady and any slight shake can result in a blurred image. This is why stabilized lenses were introduced not too long ago. These lenses offer mechanical elements that actually counteract the photographers movements to nearly eliminate any signs of shakiness.
Aperture is Speed
All lenses have a built in maximum aperture. This refers to how wide the lens’s iris can be made. There are lots of reasons to adjust aperture, but the basic reason is speed. When the aperture is closed to a small opening not a lot of light can get it. The result is a longer time to properly expose a picture. When the aperture is open to its widest then more light can get in and the exposure time can be quick.
Event photographers often work with very little light. To make the most of that light they have to have a lens that allows a wider aperture. Doing so lets them take properly exposed shots that aren’t blurred due to people moving during exposure.
The widest apertures are available on non zoom lenses but tend to be very expensive in any form.
When Glass Isn’t Glass
Cheaper lenses, especially those that come built into a compact camera, can often contain plastic lens elements. This is a big deal for people searching for perfect quality because light doesn’t travel through plastic as well as it travels through glass. Even in a real glass lens though, light will reflect and refract slightly damaging the end result.
Lenses that boast higher grades of glass are able to cut down on this. More expensive glass elements can offer close to zero refraction and reflection making them very appealing to photographers who want to print large detailed photos.
Similarly, there are different coatings on different lenses. Some coatings are there to help fight reflection while others account for things like UV blocking.
When deciding where to start, a normal lens is a good idea. From there try an ultra-wide lens because it will give you the clearest indication of what a lens actually does. Otherwise experiment with the different types and have fun.
Phil Pivnick
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