With an $899 price tag on a slow variable aperture zoom, my expectations for the optical quality for the 18-135mm were quite high. Much like with the Sony 18-105mm, however, I was slightly let down. The 18-135mm produces very good central sharpness throughout the zoom and aperture range, and even produces fairly good border sharpness in the middle part of the zoom range. However, the edges at the wide and telephoto ends of the range are only mediocre, even when stopped down to f/8.
The 18-135mm is capable of producing quality images, but nothing in them is going to blow your doors off. Both the Fuji 18-55mm and the Fuji 55-200mm show better overall performance than the 18-135mm, though perhaps that’s to be expected given the generous 7.5x zoom range. Still, given the high price tag, I was hoping for performance more in line with the 18-55. Though the 18-135mm doesn’t have the sharpness to compete with the other XF zoom lenses, it isn’t all that far behind, and the resolution produced by the lens is definitely quite good for a super zoom lens.
One thing I did notice is that the 18-135mm does seem to have just that right combination of contrast and resolution to induce the watercolor effect on X-Trans sensors in Lightroom. I noticed it popping up much more when using the 18-135 than with my other Fuji lenses. Perhaps it is the slightly lower resolution combined with high image contrast that causes Lightroom to not do so well in this case, so you may want to stick to other RAW converters when using this lens with landscape images with fine foliage detail.
Most manufacturers tend to leave bokeh as an afterthought in their super-zoom lenses, but Fuji has had a good track record in producing zoom lenses with good-looking out of focus areas. Luckily, the 18-135mm performs rather well in this area. The out of focus areas with the 18-135mm are quite pleasing in most circumstances, with smooth specular highlights and even gradation. While it can get a little busier at shorter focal lengths, it’s still a solid performance for a lens in this range.
Contrast, Color and Chromatic Aberration
The XF 18-135mm produces punchy images with good contrast and rich color throughout the zoom range and right from wide open. If you like the look of most of the other Fuji XF lenses, you’ll appreciate the 18-135mm, as it is definitely cut from the same cloth in this department.
The lens does have some visible lateral chromatic aberration, especially towards the edges of the image frame, though it’s really only prominent with light-colored areas of fine detail. While this can mostly be corrected in post-processing, there is some residual loss of detail as a result of the CA. Longitudinal CA and fringing didn’t appear to pose a problem in my daily shooting.
Distortion, Vignetting and Flare
The Fuji 18-135mm handles distortion rather well for a zoom with this range. The wide-angle end has a fair bit of barrel distortion, but nothing particularly egregious. This can be fixed rather easily with basic distortion correction tools in situations where it’s noticeable. As it moves towards the long end there’s a bit of pincushion distortion, but again, not particularly noticeable. Overall, I was quite pleased with the performance here.
There is some vignetting as well, though it usually only can be spotted in areas of even illumination and little detail, such as the sky or smooth walls. I didn’t shoot against the sun all that much in my time with the lens, but in the few images I did shoot with the sun in the frame, the lens maintained good contrast with no visible ghosts.