Canon's PowerShot S90 compact digital camera is one of the most powerful point-and-shoot models that you can slip into your shirt pocket. Much of the S90's appeal comes from its ability to overcome the shortcomings that often cripple compacts: it performs well in low light, has the option to capture in Raw format and it features an impressive set of controls that allow you to adapt the camera to just about any lighting situation.
The Canon PowerShot S90 compact digital camera can hide beneath a deck of playing cards. Its body measures 100x58.4x30.9mm and weighs 175g. You can slide it anywhere you have a spare pocket. It weighs half as much as its big brother, Canon's PowerShot G11, yet includes the same 10Mp, 1/1.7-inch CCD sensor and Digic 4 image processor. Both cameras feature crystal clear 461,000-dot LCD screens, but the S90's display is a 3in fixed-back version compared to the 2.8in vari-angle version on the G11.
You may wonder why the Canon PowerShot S90 compact digital camera captures only 10Mp while many of today's compacts can shoot 12Mp or more. The thinking is that if you put fewer pixels on a larger image sensor, you can better control image noise at higher ISO settings. Canon then developed a high-sensitivity system for its image processor to help optimise the data from low light shots. The result is that you can shoot at ISO 400, 800 and even 1,600 without destroying the image quality. This is a major step forward for a compact camera that sells for around £355.
The lens itself is an important component in this equation. The Canon PowerShot S90 compact digital camera includes a 3.8X optical zoom that has a maximum aperture of f2.0 for the 28mm wide-angle, then adjusts down to f4.9 for the 105mm telephoto. This means that when you shoot at 28mm, you have a very bright f2.0 lens that lets in a lot of light. Even at the 35mm zoom setting, the maximum aperture is f2.5, and at 50mm, a reasonable f3.2. The upshot is that the S90 features a lens that's extremely well suited for low-light photography.
Unlike many compacts, the Canon PowerShot S90 compact digital camera offers lots of control over the exposure and colour settings. The S90 features a mode dial on top of the camera, a control ring on its front and a control dial on the back. You rotate the top mode dial with your thumb to choose one of these exposure modes: auto, program, shutter priority, aperture priority, manual, low light, scene, movie and custom.
The rotating control ring around the lens on the front of the Canon PowerShot S90 compact digital camera is a true innovation. It's programmable, giving you the following choices: ISO, exposure compensation, focus, white balance or step zoom. All these functions are handy, but we preferred the step zoom setting allowing us to click-stop between 28, 35, 50, 85 and 105mm lens magnification. It feels very much like using a zoom on a digital SLR. Canon also uses the control ring to let you fine tune Auto White Balance. When you select the AWB function, you can warm up or cool down the color by rotating the ring to the left or right. I absolutely love this feature.
The control dial on the back of the Canon PowerShot S90 compact digital camera isn't as exciting, although it's a quick way to fine tune the settings you've already established with the other dials. For example, when you're in programmed auto exposure, the back control dial can let you adjust exposure compensation. The problem is, there's no way to disable it. If you're not careful, you can accidentally brush your thumb against it and change the settings without noticing. Since the control dial is contextual, we recommend you program it to do the least amount of harm. We often shoot in aperture priority mode with the control dial used for changing the aperture settings. That way, if we accidentally brush it, we don't mess up our exposure, only changing the f-stop. In future models of this camera, we would like a way to disable this dial when we don't need it.
The Canon PowerShot S90 compact digital camera provides a variety of image sizes to choose from. In Jpeg mode, you can choose from Large (3648x2736), Medium 1 (2816x2112), Medium 2 (2272x1704), Medium 3 (1600x1200), Small (640x480), Widescreen (3648x2048) and Low Light (1824x1368). The Low Light setting is accessed via the mode dial on top of the camera represented by the candle icon. The other Jpeg settings can be changed using the Function button on the back of the camera.
You also have the option of shooting in RAW (3648x2736) and process the files using the bundled Digital Photo Professional software by Canon, or by using Adobe Lightroom 2.6 or Adobe Camera Raw 5.6. If you want to shoot Raw+Jpeg, press the Menu button and choose that setting from the list of options. Shooting in Raw allows you to tap every ounce of image quality out of the Canon PowerShot S90 compact digital camera, and it's an option you rarely see in a model this size.
In addition to the control dial on the back of the Canon PowerShot S90 compact digital camera, there are a few other improvements we'd like to see. It does include a movie mode, but only captures at Standard Definition (640x480 @ 30fps). This seems odd because with its relatively large CCD sensor, image stabilised lens and HDMI output port, this camera seems perfectly designed for HD movie capture.
There's no optical viewfinder, but the 3in LCD is very good. But that does mean that you have the LCD constantly on, which drains on the battery. In our tests, we could leave the LCD screen on for about 2.5 hours straight before the battery drains. If you're shooting all day, you're going to need an extra battery. Better battery performance would be welcomed, realising that the Canon PowerShot S90 is a compact digital camera and that the battery can only be physically so big.
The Canon PowerShot S90 compact digital camera is the best pocketsize model we've seen. Even though it’s a fraction of the size of a digital SLR, it provides many of the features we value in larger cameras: a fast lens, a RAW option and high ISO capture. It’s not perfect by any means. You’ll need an extra battery, the burst mode isn’t snappy and there’s still that nagging shutter lag that we usually have to endure with cameras of this type. But the Canon PowerShot S90 takes great pictures in just about any lighting situation and provides easy-to-use, intelligent controls to do so.