The SD600 lacks certain features, such as built-in memory, image stabilization, manual exposure control, and a live histogram. These would have been handy, but they're not critical, and their absence hardly hurts the camera's appeal.
The Canon PowerShot SD600 boasts excellent performance, with fast start-up and responsive shooting. The quick shutter lags no more than 0.7 second, even in dim light. We measured a quick shot-to-shot speed of 1.5 seconds, which bumps up only slightly to 2.1 seconds with the flash enabled. Burst mode proves equally fast, delivering about 2.1fps.
Of course, the most important aspect of the camera is photo quality, and this compact shooter delivers in almost every respect. Besides exhibiting Canon's signature smooth, noiseless images at ISO 80 and ISO 100, the SD600 manages very well to as high as ISO 800, a sensitivity many compact digitals don't even reach. At that speed, the SD600's pictures are noisy but in an unobtrusive, almost filmlike way; ISO 800 images on the SD600 actually look a bit better than many other cameras' images shot at ISO 400. The SD600's ISO 200 shots are almost indistinguishable from those taken at ISO100, and its ISO 400 images are still very usable, though noise starts to become noticeable at that setting. With less noise than usual, this camera performs better than other cameras in its class, especially in low-light, no-flash conditions such as indoor performances and museums.
It's hard to find any fault with the SD600's imaging pipeline. Colors are appropriately warm and saturated at all speeds; it produces very sharp and detailed pictures. The camera's automatic white-balance and exposure decisions are consistently accurate and pleasing. Lens distortions such as vignetting or pincushioning are negligible in the SD600, though as with many ultracompacts, lens sharpness falls off dramatically in the upper-left corner of the scene. Fringing is also barely there, even under heavily backlit objects such as branches against a sky. Ugly JPEG processing artifacts such as color banding and halos around high-contrast edges are, likewise, hard to spot.