In our lab tests, the PowerShot SD950 IS performed well for a 12-megapixel model, though that still makes it slower than some of the other SD models that have fewer megapixels. The camera took 1.3 seconds to start up and capture its first JPEG. After that, it took a slightly sluggish 2 seconds between shots with the flash turned off and 3.5 seconds between shots with the flash turned on. Shutter lag measured a pleasing 0.5 second in our high-contrast test and 1.2 seconds in our low-contrast test, which mimic bright and dim shooting conditions, respectively. In continuous shooting mode, the SD950 IS fell just short of its fancier cousin, the G9, clocking an average of 1.6 frames per second regardless of image size.
Image quality from the SD950 IS is very impressive and clean at lower ISOs. Colors are accurate and well saturated, and exposures tend to be accurate, even in some tough situations. For example, the camera did a good job of balancing the built-in flash with the ambient light from the lamp in our test scene, though it wasn't quite powerful enough to pull significant detail out of the dark fur of the plush ape in the scene. Canon does an excellent job of keeping ISO noise under control through ISO 200. At ISO 400, noise becomes noticeable on monitors, but shouldn't cause problems with prints and doesn't cause any noticeable loss of shadow or fine detail. At ISO 800, noise becomes much more noticeable and some, though not all, shadow detail is lost while most fine detail remains. That said, you should still be able to get decent prints, especially at smaller sizes. At ISO 1,600, noise becomes very heavy and most shadow and fine detail, such as text and the markings on the measuring tape in our scene, is lost. I suggest staying below ISO 1,600 when shooting with the SD950 IS and staying below ISO 800 whenever possible.
For a 12-megapixel compact camera, the PowerShot SD950 IS fares well. But, if you don't feel you need so many pixels, and unless you plan to print 11x17-inch images regularly, then you can probably get faster performance by choosing a camera with fewer megapixels, such as Canon's 8-megapixel PowerShot SD870 IS--but you will have to give up the optical viewfinder if you do.
(Shorter bars indicate better performance)
(Longer bars indicate better performance)