The Canon EF-S 15-85mm is for sure a desired lens ... Providing you can obtain a good one (mine had somewhat of a QC problem). In general the resolution is excellent from 15mm through 50mm while you should plan on seeing a little softness of the borders at the 85mm long end. A sore spot of this lens is the
tremendous quantity of vignetting at 15mm @ f/3.5.
The slight shading of edges of 1.94EV epitomizes a new negative mark- the
lens is obviously somewhat poorly designed in this area . However, stopping
down some takes care of most of the issues. The large amount of distortion
is usual for this type of lens (with heavy barrel distortion at 15mm). Also,
lateral CAs become visible at both extreme endings of the zoom spread.
The lens build quality is on the very good side and definitely an edge up over the previous consumer Canon zoom lens. Predictable for Canon lenses is a ring-style USM while the AF operation is most remarkable. The Canon IS ("Image Stabilizer") functions very well within its limitations but that's already a given technology today and nothing new any longer. Overall I'd say the lens is a bit over-priced in relation its performance but the street and internet prices will eventually drop to more realistic
Feb 15, 2011✓
• Wide Focal Range
With 84° to 18° angle-of-view, the Canon EF-S 15-85mm f/3.5-5.6 IS USM Lens
provides excellent wide angle to telephoto focal lengths with Canon APS-C EOS Digital SLRs.
• Lightweight and Compact Design
Measuring just under 4" in length and weighing about 1.25 lbs, the lens is easy-on-the-shoulder while maintaining a convenient range of optical choices when composing still or video imagery.
• Optical Image Stabilization
Canon's Image Stabilization system allows you to shoot sharp images with a 4-stop advantage under less-than-optimum lighting conditions.
• Ultra Sonic Motor (USM)
Canon's Ultra Sonic Motor (USM) technology enables fast and quiet focus control with on-demand manual override when shooting in AF mode.
• Optimized for Canon APS-C Sensor Cameras
As with all Canon EF-S optics, the Canon EF-S 15-85mm f/3.5-5.6 IS USM Lens is designed to deliver optimum sharpness edge-to-edge when used with Canon APS-C format DSLRs.