Power Pop-up & LCDThe 3.0-inch LCD has proven excellent in bright field conditions, as well as in dark spaces. In the menu the rear LCD's brightness can be boosted for extreme conditions, but the middle and low-end brightness settings have worked well in direct sunlight to indoor incandescent lighting. An added benefit of dialing the LCD down to the middle to lowest settings is that the battery life is extended. Canon built in a nice shortcut to quickly brighten and darken the LCD with the press of the "Disp." or display button on the rear of the camera under the scroll wheel. The placement could not be better suited for a quick thumb press to either brighten or darken the screen. The small pop-up flash is mighty powerful for such a small package. Light emitted from the flash is evenly distributed in most instances, and does a good job of exposing the scene. In aperture priority, shutter priority, custom, and program the flash has numerous customizable settings available: auto/manual, flash exposure compensation from -2 to +2 in 1/3 increments, and 1st-curtain/2nd-curtain flash sync. These features are excellent and missed in manual. It is interesting how Canon left flash exposure compensation off of flash options in manual. This is a feature that is missed and will hopefully be included in a software update in the future.
From Canon S90 Review