Standard zooms, which usually cover the 18-55mm range, are ideal general-purpose lenses. With the standard field of view that equates to the eye at around the 35mm mark on most consumer DSLRs, these lenses go from a little bit wideangle to a little bit telephoto.
This makes them suitable for the majority of the kinds of shots that most people take on a regular basis, from scenic views to portraits.
The kit zoom lenses supplied with most DSLRs do a fairly remarkable job considering that they're designed to be as cheap as possible to make, so that they add as little as possible to the cost of buying a new camera.
The image quality of these lenses is more than adequate for general snaps but take away the budgetary constraints and it's possible to produce optics of markedly superior quality.
However if you aspire to produce images of the highest technical standard, possibly at big sizes, you'll be looking to upgrade the kit lens for a higher-end standard zoom before too long.
They'll probably be a lot bigger and heavier but they'll have wider maximum apertures and far superior edge-to-edge resolution, due to the use of technology such as aspherical lens elements and extra low dispersion glass.
Here are four good options in a range of lens mounts...
This premium grade lens from Sigma carries the distinction of being the world's first standard zoom to offer a constant f/1.8 aperture throughout its range.
This improves its performance in low light and also enables it to create an extremely shallow depth-of-field effect when opened right up.
Image quality is excellent with no signs of colour fringing and only minimal distortion at the extreme ends of the focal range.
Lens Mount - Nikon F, Canon EF-S
Construction - 17 elements, 12 groups
Filter Thread - 72mm
Weight - 810g
Canon's revamped 24-70mm lens improves on the standard zoom that has long been a favourite of professional photographers. Build quality is excellent and resolution never falls below the critical 0.25 cycles-per-pixel.
In laboratory testing some slight colour fringing does appear at the shortest focal lengths, however this is almost impossible to detect in real-world use.
Overall, this lens represents a solid choice for professionals and well-heeled enthusiasts.
Lens Mount - Canon EF (full-frame)
Construction - 18 elements, 13 groups
Filter Thread - 82mm
Weight - 805g
Whereas most kit lenses typically offer a focal range of 18-55mm, this entry-level zoom extends telephoto reach to a handy 105mm, allowing you to get a little bit closer to your subject.
Given that the lens is designed specifically for use with APS-C equipped DSLRs, this equates to 27-157mm in full-frame terms.
Sharpness is pretty impressive throughout the range, however some colour fringing is noticeable despite the use of ED glass. That aside, it's a great lens for the money.
Lens Mount - Nikon F (DX)
Construction - 15 elements, 11 groups
Filter Thread - 67mm
Weight - 420g
Thanks to the 2x crop factor inherent to Micro Four Thirds sensors, this premium 12-35mm lens provides the 35mm equivalent of 24-70mm.
As a flagship G-series model, the lens offers a constant f/2.8 aperture along with built-in Image Stabilisation.
Image quality is excellent with lab tests producing an excellent set of MTF curves; resolution remains at or above 0.3 cycles-per-pixel between f/2.8 and f/16, and only at f/22 does resolution dip below the critical 0.25 cycles-per-pixel.
Lens Mount - MFT
Construction - 14 elements, 9 groups
Filter Thread - 58mm
Weight - 305g