Canon's 18-55mm 1:3.5-5.6 IS is the latest in its line of inexpensive DSLRs kit lenses which began with the original 18-55mm in 2003, as an accompaniment to the groundbreaking EOS Digital Rebel/300D (widely considered to be the camera which started the affordable DSLR revolution). The focal length range was chosen to be equivalent to the popular 28-90mm kit lenses then available for entry-level 35mm SLRs, and lightweight plastic construction was used to keep costs down. The design was slightly refreshed with the introduction of a mk II version to accompany the Digital Rebel XT/350D, however this only really featured subtle cosmetic changes, with no improvement to the optics. And those optics were never the strong point of this lens, which gained a reputation as a somewhat mediocre performer, with many users looking to upgrade fairly rapidly.
But Canon has now produced a major upgrade in the shape of this IS version, which looks destined to become the new standard kit lens for Canon's APS-C dSLRs such as the EOS 450D. IS stands for Image Stabilization, and the new lens features a wholly new, simplified optical image stabilization module, which Canon claim offers similar performance to that offered in their higher end (and hitherto much more expensive) IS lenses. This new lens is a clear response to the competitive threat posed by other manufacturers offering sensor-shift stabilization in relatively inexpensive DSLR bodies, so the big question is whether it can deliver the goods in terms of image quality, in the face of some strong competition at this entry-level point.
Changes compared to the non-IS versions
Side-by-side comparison of the 18-55mm IS to the non-IS mk II version suggests that it offers more than simply the addition of an IS unit. The new lens is slightly longer than its predecessor (70mm vs 66mm), and the front element is substantially larger in diameter (44mm vs 37mm); the optical diagram reveals that the next three elements are also larger, presumably to accommodate the demands of the optical IS unit. The aperture diaphragm has been moved rearwards in the lens assembly, and the lens coatings also appear to have been changed. However the lens remains impressively lightweight and compact; addition of the IS unit adds nothing to its diameter, and just 10g to the weight. As an added bonus, the minimum focus distance has been reduced from 0.28m to 0.25m, offering a welcome increase in maximum magnification from 0.28x to 0.34x. Overall this represents a pretty impressive technical achievement by Canon’s lens designers.
Headline features
- 29-88mm equivalent focal length range
- Optical image stabilization – 4 stops
- EF-S mount for Canon APS-C DSLRS only
Angle of view
The pictures below illustrate the focal length range from wide to telephoto:
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