Canon EF-S 18-200mm f/3.5-5.6 IS Review

Being an EF-S design this zoom is one of only a handful of lenses in Canons range that is suitable for use only on APS-C digital SLRs. Buyers who might be thinking of upgrading to a full-frame body in the future could be tempted to steer away from this lens for that very reason but there is no full-frame equivalent, so this zoom must be assessed in terms of what it is rather than what it is not (for the record, Canons closest full-frame zoom at around the same price point is restricted to a zoom range of 28-135mm).

The lens is fairly weighty and has a reassuring, solid feel. There is a broad zoom ring in the middle of the lens barrel with a narrower focus ring further forward and a pair of mode sliders (AF/MF and IS On/Off) to the rear. Sadly, the focus ring rotates in AF mode and care must be taken to avoid obstructing it. Also regrettable is the omission of a lens hood.

The zoom action is very smooth and offers just the right amount of resistance across its 90mm throw.
The AF system is brisk and reasonably quiet. In addition, Canons Image Stabilisation (IS) system is a dream: it has none of the jerkiness or clunks that afflict some other designs.

In terms of technical testing, chromatic aberrations were seen at both ends of the zoom range when photographing the MTF test targets. Unfortunately, field testing revealed that pictorial scenes also displayed signs of colour fringes at the 200mm setting. Sharpness was good-to-excellent at short and medium focal-lengths but declined noticeably at the 200mm setting. There was also a significant loss of sharpness at small apertures: settings of f/22 and downwards should certainly be avoided.

sample images

Verdict

Overall, however, this is a very impressive lens given its 11x zoom range. The weaknesses noted above should not be given undue weight as there is no denying the fact that this is a versatile and capable lens that has the potential to keep APS-C users happy for many years to come.