The new Micro Four Thirds cameras from Olympus and Panasonic may have grabbed all the headlines recently, but Olympus at least seems committed to carrying on with the regular Four Thirds format too. (Remember, Four Thirds is the conventional SLR design, Micro Four Thirds is the smaller, mirror-less version.) Indeed, Olympus’s latest E-620 digital SLR is very good and has done much to close any perceived gap between Olympus’s D-SLRs and the rest.

But there is a complication. The slightly smaller sensor size of Four Thirds cameras means firstly that you have to apply a 2x focal factor rather than the usual 1.6x to work out a lens’s equivalent focal length. Therefore if you want an 18-36mm equivalent zoom, you’re looking for a 9-18mm lens, and they don’t exist outside the Four Thirds format (though Sigma’s 10-20mm comes close – more on that later).

It looks like you’re pretty much stuck with the Zuiko Digital ED 9-18mm f4.0-5.6, then, though ‘stuck’ is perhaps not quite the right word because it’s actually a pretty good lens. Our test charts show good definition at all apertures and across the zoom range, and while the edge definition generally lags slightly behind the centre definition, it’s not by enough to be obvious in photographs.

There’s some noticeable barrel distortion at 9mm, but not as much as you’d expect from the average kit lens at its shortest focal length. This changes into very pincushion distortion at 18mm, but it’s so mild you probably won’t notice it in everyday photography. There’s not that much chromatic aberration, either. You can spot it near the edges of the frame at shorter focal lengths, but it’s no worse than other lenses of this type, though it can become noticeable where objects are silhouetted against a bright background. The zoom range is pretty modest at just 2x, but again it’s typical for this kind of lens.

Overall, the 9-18mm performs pretty well, optically. It’s light to carry around and has a smooth, short zoom action too. The lightweight feel does make it feel a little on the cheap side, but that’s just an overall impression – everything works fine and feels perfectly solid.

If you’re looking for a step up in performance and build quality, though, there is another option. This 9-18mm is part of Olympus’s ‘Standard’ lens range, but there’s also a ‘Top Pro’ range which includes the Zuiko Digital 7-14mm f4.0, and this gives an equivalent focal range of 14-28mm, which is wider still, along with much meatier, pro-level build quality. But with a price tag of around £1,400, it’s almost £1,000 more than the 9-18mm and will probably only appeal to professionals.

We mentioned that the smaller sensor size of Four Thirds cameras produced a different ‘focal factor’ for calculating lens focal

lengths, and this does affect the availability of third-party alternatives. There are no independent lenses this wide, and precious few which come in a Four Thirds mount.

There is one, though: the trusty Sigma 10-20mm f4-5.6. On a Four Thirds camera, this is equivalent to 20-40mm, so it’s not far off the Olympus lens’s 18-36mm range. The trouble is that it’s not far off its price, either. Currently, the Sigma seems to be selling for around £400, which is only £50 less than the Olympus lens and it doesn’t quite match its wideangle capability either.

So really, considering that it’s an own-brand lens, this Zuiko Digital 9-18mm is pretty good value. It’s light and smooth to operate, it performs well and, for a lens of its type, it’s not particularly expensive.

Final Verdict The little Zuiko Digital 9-18mm is competent rather than stunning, but it’s pretty good value for an own-brand lens, and there’s precious little competition OVERALL

Our lens reviewer, and technical expert, Rod is a veritable photographic encyclopaedia. His illustrious CV has seen him write for many mags, websites and journals.