The 18-55mm VR performed pretty well in our studio tests, at least on a par with the other kit lenses we have tested. It perfoms best in the middle of its range, with a distinct drop in preformance towards the telephoto end, as is common with lenses of this type.
|Sharpness||An impressive performance at 35mm, where sharpness is high across much of the frame at F8, contrasts with a rather less desirable set of results at 55mm. Here the lens is soft across the most of the frame wide open, although it improves dramatically at F8-F11. As usual, stopping down beyond F11 causes the image to degrade due to diffraction, and anything below F16 starts to look distinctly soft.|
|Chromatic Aberration||As usual, chromatic aberrations are highest at the wideangle settings (18mm and 24mm), and become essentially negligible at telephoto. Blue/yellow CA is particularly well-controlled; overall this is about as good a performance as you'll get from a kit lens.|
|Falloff||We consider falloff to start becoming a potential problem when the corner illumination falls more than 1 stop below the centre. The 18-55 VR performs quite well here, with falloff only likely to be an issue wide open at 18mm and 24mm, and disappearing on closing the aperture one stop.|
|Distortion||As usual distortion is most pronounced at wideangle, with a rather pronounced 2.2% barrel at 18mm. The observed distortion pattern is relatively simple, with little recorrection towards the corners, so it should be reasonably easy to correct in software if desired. The lens is almost perfectly rectilinear at 35mm, and switches to mild pincushion at longer focal lengths.|
Specific image quality issues
As always, our studio tests are backed up by taking hundreds of photographs with the lens across a range of subjects, and examining them in detail. This allows us to confirm our studio observations, and identify any other issues which don't show up in the tests.
It's a kit lens, and the 18-55mm VR is therefore rather prone to flare in bright light, with the shallow hood unlikely to help much especially at longer focal lengths. The lens performs quite well when the sun is actually within the frame, showing an overall loss of contrast plus a few coloured flare patches even stopped right down to F16. Here the 7-bladed aperture gives 14-point 'starburst' patterns, which some people apparently value quite highly.
The greatest problem, however, comes from strong back or sidelit conditions, with the sun shining directly onto the front element but outside the frame itself. Unfortunately the 18-55mm VR handles these situations particularly badly, especially at the telephoto end where almost half the frame can become covered with multi-coloured blotches of flare. And these aren't the kind of pretty patterns which Adobe's programmers have tried so hard to mimic with the 'Lens Flare' filter, but instead downright ugly and destructive of anything which was supposed to be in the picture.
I'd suggest the best option with this lens would be to buy a multi-angle acrew-in rubber hood which can be adjusted to provide a deeper shade when shooting at 55mm; this can cure flare problems almost completely.
|18mm F16, sun in corner of frame||55mm F8, strong sidelight|
Background blur ('bokeh')
One genuinely desirable, but difficult to measure aspect of a lens's performance is an ability to deliver smoothly blurred out-of-focus regions when trying to isolate a subject from the background, generally when using a long focal length and large aperture. This lens's 55mm F5.6 setting scarcely counts as either, so genuinely blurred backgrounds aren't terribly easy to obtain.
When defocused backgrounds do appear, they aren't all that smooth either, showing harsh sharp edges to specular highlights. To be fair though, this is pretty typical of this type of lens, and one of the reasons true macro lenses aren't cheap.
|100% crop||55mm F5.6|
Nikon claim that the 18-55mm's Vibration Reduction system allows handholding at shutter speeds three stops slower than normal when shooting at 55mm focal length, and real-world shooting suggests that this is a pretty reasonable estimate. The VR unit is near-silent in operation, with just-audible clicks as the VR unit unlocks and locks at the start and end of operation.
We tested the VR system at both the long and short ends of the zoom range in our standard studio test. We take 10 shots at each shutter speed and visually rate them for sharpness. Shots considered 'sharp' have no visible blur at the pixel level, and are therefore suitable for viewing or printing at the largest sizes, whereas files with 'mild blur' are only slightly soft, and perfectly usable for all but the most critical applications. With the 18-55mm's equivalent focal length range of 28-82.5mm, we'd normally expect to be able to get good results handheld without image stabilisation at 1/50 sec at wideangle, and 1/100 sec at telephoto. The subject distance for these tests was approximately 2.5m.
|18mm VR OFF||55mm VR OFF|
|18mm VR ON||55mm VR ON|
These results demonstrate that you no longer need to pay an arm and a leg for a lens with an effective VR system for your Nikon dSLR. We see an approximate 2 stop improvement in 'hand-holdability' at wide angle, with a 90% success rate of critically sharp shots at 1/13 sec when VR is turned on, as opposed to 1/50sec without. There's even a 50% chance of getting a usable shot at shutter speeds as low as 1/3 sec, which is essentially impossible handheld without stabilisation.
At the telephoto end results are similar, with the VR again offering about 2 stops of stabilisation, and giving a good chance of getting usable results at shutter speeds as low as 1/13 sec. It's also worth noting that this performance is essentially identical to that which we obtained from the much more expensive Nikon 18-200mm VR, showing that no corners have been cut given the relatively low cost of the 18-55mm VR.