The A650 IS' pictures look great, especially at lower sensitivity levels. The camera's 12-megapixel photos display loads of fine detail, from fine text to pet fur, with a generous dynamic range.
Noise starts to become noticeable on computer monitors at ISO 200, and begins to appear on prints at ISO 400 and higher. The noise doesn't become too problematic, however, until ISO 800, where distinct fuzz covers pictures, muddles colours, and obscures details.
From ISO 1,600 to the camera's maximum sensitivity of ISO 3,200 -- accessible as a scene preset that lowers the resolution to 2 megapixels, rather than through the ISO button -- the pictures become downright unusable. Again, these noise levels surprise us very little, as nearly every 12-megapixel camera tested produces similar noise.
The photos aren't entirely without flaws, however. Prominent purple fringing tends to appear on contrasting edges, with higher ISO levels making them look even worse. At the widest position, the A650 IS' lens produces some barrel distortion, as well. You can't readily detect the distortion without a grid, however, and both the distortion and fringing present only minor problems in the camera's pictures. If you shoot at low ISO settings, you can count on generally excellent photos.
With its great picture quality and wealth of features, the Canon PowerShot A650 IS makes a great camera for amateur photographers who either don't want to step up to a dSLR yet, or who simply want a secondary camera alongside their SLR. Despite its performance and noise issues, the A650 IS presents a fine choice for a flexible, high-resolution, photographer-friendly camera.
Additional editing by Shannon Doubleday