Best zoom lenses | Space

A zoom lens is one that allows you to adjust its focal length. They can be wide-angle, telephoto, or form the bridge between the two, but they’re all adjustable. The opposite to a zoom lens is a prime, and these lenses tend to offer faster apertures to make up for being stuck at a single focal length. Zooms are extremely versatile lenses, and just about every photographer has one or two in their kit alongside their best camera.

The faster, or wider, your aperture (the lower the f-number) the more light the lens lets in, and in zoom lenses this tends to top out at f2.8, although a very few are making it to f2. If you’re looking for the best lenses for astrophotography, then you’ll naturally gravitate toward the faster apertures, but don’t rule out slower lenses too. With a star tracker, you’ll be able to use longer exposures to compensate, and longer lenses’ ability to peer more deeply into the cosmos rivals some telescopes.