Overall, the PowerShot G7 is a well-designed camera. In many ways it has the feel of an old-fashioned rangefinder camera, including a solid, hefty metal body and buttons and dials galore. The ridged plastic ring hides a bayonet mount for add-on adapters.
Canon piles on the adjustment and navigation features in this set of concentric controls. The outer ring is a scroll dial for navigating menus and adjusting exposure and focus; the inner ring operates like a traditional four-way navigation/quick access switch. And the Set/Func button pulls up the menu for shooting options.
The dedicated dial for ISO settings contributes to the cameras retro feel. As you turn the dial, the different values also appear on the LCD, so you don't have to move the camera to look at the top if you've already framed a shot.