In addition to altering the overall design, Canon opted to replace its more traditional four way navigation switch with a four way nav plus wheel. The wheel scrolls through some of the modes that you used to pull up via the function (Func) button, such as Stitch Assist, Color Swap, Color Accent, and Digital Macro, as well as the scene modes. The Func button sits in the middle and calls up exposure compensation, white balance, My Colors, metering, compression quality, and image size.
Within this menu and within the menu system in general you can use either the nav switch or scroll wheel. A mode switch, which doubles as a thumb rest, toggles among automatic, manual, program exposure (scene), and movie capture modes. Normally, I'm a big fan of scroll wheels. But I find the free flying wheel of the SD890 IS too difficult to control.
There's no physical feedback so you can't feel you've scrolled to the next option, and I frequently found myself either zipping past my choice or frustrated because it didn't seem to be changing.If you pause to figure out which option it's going to stop at Canon should have called it the roulette wheel the options time out and disappear.
Furthermore, when operating the menu, display, and review buttons, my thumb tends to drag the wheel with it.
Finally, though the mode switch works fine for its function, it's neither big enough nor shaped comfortably enough to rest your thumb. I was tempted to give the camera a lower rating for design, but I suspect other users won't find it quite as annoying to use as I do. The f/3.2-f/5.7, 37mm-185mm equivalent lens represents the most notable change from the SD850 IS.
Though a broader zoom range, it's considerably slower (the maximum aperture rises to f/3.2 from the SD850 IS' f/2.8) and slightly narrower (37mm equivalent compared to the SD850 IS' 35mm). That's not necessarily a trade off you want to make.
The wider angle lenses on models such as the SD870 IS and the Panasonic Lumix TZ models make them more flexible for typical snapshots of groups or landscapes, and it's not as if the SD890 IS' zoom reaches far enough to buy you other shots you might not normally get. Features carried over from the SD850 IS include face detection and optical image stabilization; features missing from both cameras include no semi manual exposure modes, such as shutter and aperture priority.
