Canon's PowerShot S series has previously consisted of compact cameras for enthusiasts, but the PowerShot S110 is less so, despite its fast-ish lens, support for raw format, and manual exposure controls. Canon made a few changes in its replacement for the popular S100, including much-needed improved autofocus performance, but the image quality hasn't really changed despite a new sensor. And the most welcome new feature, support for wireless uploading, is implemented annoyingly and replaces the S100's geotagging capability. Yes, it's still the smallest camera available in its class, and a lot of people will continue to be attracted by the fact that it has a 5x zoom lens compared with the faster but less zoomy lenses on slightly more expensive models from Panasonic, Samsung, and Olympus. But the photo quality isn't sufficiently better than that of cheaper, full-featured point-and-shoots that cost a lot less.
Despite the change in sensor, the S110's image quality is very much like the S100's. For its price, quality remains what I'll call "borderline excellent" -- that is, a lot of people will be very happy with it, and raw shooters can get very good results. ISO 800-and-lower photos that didn't stand up to scrutiny on a display viewed at 100 percent still look good printed at 13x19. But pickier photographers will likely want to pay more for something like the Sony Cyber-shot DSC-RX100 and get unambiguously better photos.
This is not a camera that excels in low light. You can get usable JPEGs as high as ISO 400 but processing raws delivers better results at all ISO sensitivities, mostly because you can minimize the edge artifacts that way. At ISO 800 images look fine scaled down to about 50 percent; at high sensitivities they're okay for small Web posts or viewing on smaller mobile devices. As with many small-sensor cameras, the in-focus areas of higher-sensitivity shots can look fine, but the out-of-focus areas become seriously mushy because of the necessarily aggressive noise reduction.
While the color rendering looks fine overall, I did find daylight white balance a little cooler than I like. The camera's dynamic range is pretty good, with a reasonable amount of recoverable detail in highlights and shadows, though as with its dSLRs, Canon's default color settings push the contrast too much, which results in clipped highlights and shadows in the JPEGs. You can adjust the settings to resolve that, however.
Overall, the video quality is fine for typical movies -- kids, pets, vacations, and so on. In bright light there's some highlight clipping but no serious artifacts. In low light the video looks noisy, but it's acceptable and no worse than you see from competing cameras.
Editors' note: We recently updated our testing methodology to provide slightly more real-world performance, so the results aren't necessarily comparable with previous testing. Until we're finished refining our procedures we will not be posting comparative performance charts.
Although the S110 gains some speed over the S100 for autofocus, its processing remains relatively slow and lags behind a lot of the competition (unfortunately common for Canon's enthusiast compacts). It powers on, focuses, and shoots in about 2.3 seconds, mostly due to the wait for the lens to extend. Time to expose, focus, and shoot in good light runs a fast 0.2 second, rising to an equally good 0.4 second in darker conditions. Like the S100, though, the camera gets bogged down with processing, slowing sequential shot times: 2.1 seconds between shots for JPEG and 2.7 seconds for raw, bumping up to 3 seconds when you need to wait for the flash to recycle. These shot-to-shot times drop a little if you're zoomed in rather than at wide-angle.
If you need to use autofocus during continuous shooting you'll get about 0.9 frames per second for JPEG and 0.8fps raw, and that's for a fixed 10 frames. Without autofocus, it rises to about 2fps for JPEG and 1.1fps for raw, and you can obtain a usably large burst run.
I'm a bit torn about the autofocus performance, mostly because of the options offered. You have two choices: single-point AF and Face AiAF. I think using the center focus point and recomposing is always the only way to guarantee a focus on the subject, because multipoint autofocus systems usually make the wrong decisions and simply focus on whatever's closest in the scene. Regardless, the majority of point-and-shoot photographers use the latter. But face-detection modes tend to have a lot of false positives in scenes without people -- mistaking facelike objects for faces -- so I think Face AiAF works worse than standard AiAF in some shooting scenarios. The single-point AF works pretty well (despite pulsing a bit in continuous mode when shooting video) and that's what you should be using; the more traditional multipoint doesn't work well at all.
The lens also remains a disappointment on this camera. Though it has a longer zoom than some of the S110's competitors' lenses, the aperture also narrows very quickly (and it starts out narrower) and you end up needing a lot of light simply to shoot at the longest focal length -- even more than at comparable focal lengths for cheaper cameras. If the high-ISO-sensitivity image quality were a lot better then it might not be so much of a problem.
The touch screen operates very smoothly and remains visible enough in direct sunlight. The battery life is on the short side, though.