Overall, photo quality is excellent for this class of camera. Images do get softer and noisier above ISO 200--typical for point-and-shoots--but ISO 400 and 800 are still very usable. Like other "HS" models I've tested this year, the noise and noise reduction are well-balanced so you still get good color and detail up to ISO 800. Colors desaturate some at ISO 1600 and 3200, subjects look very soft, and detail is greatly diminished. While you might not want to view them at larger sizes or heavily crop them, the high-ISO results should be satisfactory for Web or prints at small sizes, though, again, colors will look a little off. Keep in mind, too, that if you're shooting indoors with lens extended, you'll need the higher ISOs to keep shutter speeds fast enough to prevent blur. Also, the auto white balance is warm indoors, which doesn't help color when combined with higher ISOs; use the presets or use the custom option when possible.
Canon includes a full-resolution, eight-shot-burst scene mode that is capable of shooting speeds up to 10 frames per second. This sets focus and exposure with the first shot, but that's common with these modes. There is also a continuous shooting setting that hits about 2.3fps (again, with focus and exposure set with the first shot) and a continuous with autofocus that is far slower, but at least it's an option.
The lens is, of course, the main attraction with this camera, going from 24-840mm (35mm equivalent). The image stabilization is quite good, too, though you'll still want to shoot with a tripod for the best results.
It doesn't appear that Canon does much to help remove or reduce fringing in high-contrast areas of photos. Most megazoom cameras produce a lot of fringing, but some create more at the wide or telephoto positions. The SX40 HS is bad at both ends, to the point where you'll see it in larger prints or if you crop heavily. If you're able to look past it or don't mind removing if it bothers you, then it's a nonissue.
As for lens distortion, Canon keeps the barrel distortion in check at the wide end; there was some on the left side of our review camera, but it's barely detectable. When fully extended, the lens exhibits slight pincushioning, but not enough to be concerned. Center sharpness is good and the lens softens only a bit out to the sides and corners.
Canon includes several ways to experiment with your photos. This includes settings for adjusting color, contrast, and sharpness in addition to different shooting modes like Fish-eye Effect, Miniature Effect, and Toy Camera, which was used here. Most of these can be used when shooting movies, too.
While the SX40 HS doesn't offer the a high-dynamic-range mode like other cameras in its class, Canon does include its i-Contrast feature, which helps rescue shadow detail like the face of the player in this photo. On the left is the original and on the right is the same photo adjusted with i-Contrast with the camera in playback. Take a closer look and you'll see the difference a little better.
Canon also includes exposure bracketing that will take three shots in a row at different exposures. However, it doesn't do it all that fast so you and you're subject have to be stationary.