Lens Options for Your Digital SLR
Zoom lenses aren't the only type of lenses available for your dSLR. You should know how they differ from the other options. Here are some of the alternatives to zoom lenses in general and standard zoom lenses in particular.
A prime lens has a fixed focal length. A lens with a fixed focal length can’t zoom in or out. Its magnification level is fixed from the day you buy it until your grandkids sell it on eBay.
The thing with prime lenses is that you have to buy the lens that matches the focal length you most use or like the best. When you compose your shots, you have to physically move closer or further away to zoom in and out.
Prime lenses specialize. Everything is optimized for the lens to produce the best photos at its focal length. The downside to prime lenses is the major reason why general zoom lenses are so popular: People get tired of being limited to a single focal length and the time it takes to swap lenses when you want to change it.
A wide-angle zoom lens zooms in and out, just as a general-purpose zoom lens does, but a wide-angle zoom lens has a focal length range that’s limited to wide-angle territory (under 24mm APS-C and 35mm for full-frame).
There is some focal length overlap between most wide-angle zoom lenses and general-purpose zoom lenses. The wide-angle variety will extend deeper into the wide angles, however. Ultra wide-angle lenses give you much more coverage than standard zoom lenses.
Wide-angle zoom lenses are great at what they do, but you have to want to shoot a lot of wide-angle shots for it to be worth it.
These lenses work similarly to wide-angle zooms, but with a different area of expertise: telephoto zoom. Generally speaking, a telephoto zoom lens overlaps some focal lengths that general-purpose zoom lenses cover, but they extend well into telephoto territory.
There is a lot of variety between telephoto zooms, both in the starting and ending focal lengths. Starting focal lengths tend to be in the 50–70mm range, but some begin in wide-angle territory. Ending focal lengths tend to be between 200 and 300mm.
Other specialty lenses
Other specialty lenses offer creative and artistic uses:
Macro lenses specialize in taking photos of close objects with a reproduction ratio close to 1:1. Most macro lenses are primes.
LensBaby lenses are untraditional. They come in different types that have different creative effects. Experiment with different focus effects and qualities. These lenses are incredibly fun to play with.
Holga cameras are cheap plastic film cameras that have quite a large following. They create very distinctive photos. Now you can mount a plastic Holga lens right on your dSLR. Very cool.
Diana+ are similar to Holga lenses, but have much more zoom. For example, the fisheye lens acts like a standard lens on a dSLR. Diana+ lenses require an adapter. Once you have that, you're good to go.
Tilt-shift change the orientation of the focal plane. Normally, it’s perpendicular to the camera. Tilting the lens allows you to angle or flatten it. Shifting displaces the lens in the direction of the shift, allowing you to move the subject's location without moving the camera. The objects you photograph tend to look like toys in a diorama.
Pinhole lenses are something you can easily make out of an extra body cap. (Just search online for making pinhole camera.) They have no glass. The pinhole lets light into the camera and doesn’t focus. The aperture is so small and the depth of field is large enough that you don't have to worry about focus. Expect longer exposure time. Pinhole cameras create soft, dreamy photos.
Each lens serves a purpose. Your challenge as a photographer (well, one of many) is to find the lens that suits your purpose. You will find that standard zoom lenses are so versatile, though, that they’ll meet most of your photography needs most of the time. That's what they were designed to do.