Which Lenses Should You Buy?

You aren't just buying a camera when you buy a camera; you're also buying into a lens system. You can't put a Canon lens on a Nikon body, which means when you buy that Nikon body you're effectively turning your back on every other brand of lens. That's not a bad thing, and there is no right ecosystem to buy into, but it's important to understand that that's part of the decision. These days, with very little difference between top-end cameras across brands, lenses are an important, if not more important, part of your decision.

If you know that you want to shoot a lot of night-sky shots and you have your eye on the Samyang XP 14-mm f/2.4—one of the best, reasonably-priced astro lenses available—then you also know you'll want to buy either a Canon or Nikon mirrorless camera since the Samyang is made for those mounts only.

But which lenses do you need? Cameras are often sold with what's known as a “kit lens.” These lenses tend to be lower quality, but are also a cheap way to get started. Most kit lenses are zoom lenses spanning the 35-mm to 80-mm range. I recommend beginners start with a kit lens if there's one available for the camera you've got your eye on. After you've shot with the kit lens for a while, you'll have a better feel for which focal lengths you like.

Lenses are generally divided into three basic categories: wide-angle lenses (anything from 12 mm up to 35 mm), “normal” lenses (anything from about 40 mm to 65 mm), and telephoto lenses (anything longer than 80 mm). There are also two types of lenses: zoom lenses, where the focal length changes, and prime lenses, where the focal length is fixed. Both have their place. Zooms offer more versatility, but usually have a larger f-stop, making them have less depth of field and worse low-light performance. Prime lenses are faster, meaning you can shoot wide open for that sweet, sweet bokeh, but are less versatile.

I should note that technically, you can adapt lenses from one manufacturer to another, but you often lose autofocus or spend considerable sums on expensive adapters, and the experience of using a Canon lens on a Nikon body isn't nearly as nice as a native lens.