The lens is, of course, one of the most important parts of your camera. It’s a good idea to fully understand the advantages and disadvantages of your lenses and how different lens use will affect your photographs. In this guide, we’ll look at the different types of lenses and what kind of photography you can and can’t do with the ones you have.
If you own a 35 mm film camera, then it probably came with a 50 mm “normal” lens. This lens has a lot going for it, such as being probably quite fast—f/2.0 (meaning it has an f-stop capability of 2.0, which we discuss in our Quick Guide Photography 101: Aperture and F-Stop)—or maybe even faster. It’s also lightweight and probably very sharp, even if it was comparatively inexpensive.
One of the big advantages of the 50 mm lens is that, depending on the vintage, it can be used with a digital camera of the same make. If you have a digital camera with a sensor that is smaller than 35 mm film (and most are), then your “normal” lens can become a very nice moderate telephoto for portraits when used on your digital camera. The only real drawback to the 50 mm lens is the obvious fact that the focal length is fixed (more on focal length in a minute).
If you bought a DSLR, it probably came with a zoom lens with a range of about 18 mm to 60 mm (wide-angle to moderate telephoto, respectively). It probably also has a variable maximum aperture, which means that the aperture changes as the lens changes focal lengths. Modern cameras have electronic couplings in the lens that make the variability of the aperture quite seamless in use, so you probably won’t even notice it most of the time.
“Kit” zooms such as this are incredibly versatile; they are fantastic for most casual photography. For many people, this zoom is the only lens they’ll ever need to own.
This type of lens can be prone to flare, though, so use a lens hood. They are not equally sharp at all focal lengths or apertures (sometimes they differ dramatically), and they are prone to both vignetting—where the corners and edges of the photograph appear darker than the middle—and curvilinear distortion. The small maximum aperture and inherently shorter focal lengths of these lenses means that you will have less control when using selective focus techniques.
The kit zoom lens that came with your camera is remarkably handy. Using the kit lens will help you to find “sweet spots” at certain focal lengths and within certain limitations. The kit zoom can be indistinguishable from a pro-quality lens. And if you never make prints bigger than 8″×10″, then the kit zoom might be all you ever need.
If you are starting to make exhibition prints or feel like you are getting serious about photography, you might want to upgrade your lens in the same range as your kit zoom. But remember, even pro-quality lenses aren’t universally perfect at all apertures or focal lengths. Testing is a tool to optimize the way you use your lenses.
Contrary to popular belief, most professional photographers don’t carry a virtual camera store of lenses in their bags. In fact, many famous photographers never carry more than one lens. This is because many pros and fine-art photographers have a certain focal length that they gravitate toward and shoot with most of the time. If you’ve been shooting for a while, there is probably a prime/single focal length lens that you really need. These are the lenses that are worth top dollar.
Besides the obvious optical properties, shooting with fixed focal lengths can also be good for your growth as a photographer. They make you move around a subject and think, instead of just dialing in a composition. Moving from the kit zoom to a prime is probably the most important upgrade you can make to your camera.
If you are consistently frustrated by not being able to get close enough—and simply changing your vantage point isn’t an option, then perhaps you need another lens with more length. Moderate telephoto to long telephoto, variable aperture zooms like a 70–300mm f/4.5–5.6 can be fantastic values and still be light enough that you won’t mind the extra weight in your camera bag. These are great for photographers who occasionally need a long lens but don’t make their living on long focal lengths. Fast and long zoom lenses are sexy, but the reality is that unless you really need the speed and you shoot long focal lengths regularly, you won’t want to incur the weight penalty they exact.
Professional zoom lenses are really marked by the term “consistency.” They usually have a constant maximum aperture, and the quality of the lens is more consistent throughout the zoom range. All zoom lenses have certain sweet spots, but the optical quality of professional zooms ranges from really good to awesome. Another important feature of pro-level zoom lenses is the fact that the front element doesn’t rotate as the lens is zoomed or focused, so the effect of a polarizing filter doesn’t change.
Do you find that you often can’t get back far enough to take the shot you want? Many of the ultra wide-angle zoom lenses like Canon’s 10–22mm are made exclusively for digital cameras and will not adequately cover or even fit onto full-frame 35 mm film cameras. If you only work digitally, then the “digital only” DX lenses are often significantly cheaper and perform very well. But if you like to still shoot with film or are considering upgrading to a full-frame camera like Canon’s 5D, it makes sense to buy lenses that work for both (your kit zoom won’t). Think carefully about how you will use the lens before dropping your cash on the counter.
The basic idea of the Lensbaby is that the proprietary Lensbaby lens (a simple 50 mm lens) is mounted to the end of a flexible tube that is focused by pushing or pulling the lens until you achieve the focus effect you want.
The Lensbaby isn’t exactly a precision optical instrument, but it does give you back some of the selective focus that we have lost in digital photography. They are quite inexpensive ($100–$400 depending on the model) and a fun little accessory to spice up your photography.
Because they really work best in close-up applications, you can also use the Lensbaby to gain back some of the depth of field you lose when working closely.
Now that you know what all of these lenses do, you can make the best choice for your camera and your photography needs. Your photos will thank you! For more photography information, check out our Quick Guides Photography 101: Aperture and F-Stop and Photography 101: The Basic Conventions of Composition. Happy shooting!
From The Complete Idiot’s Guide to Photography Essentials by Mark Jenkinson