Compared to...

Below you will find a studio comparison between the Sony DSC-S90 and the Canon PowerShot A520 at ISO400.

Studio scene comparison (@ ISO 400)

• Sony DSC-S90 : Program mode, ISO 400, Default Image Parameters,
  Manual white balance (preset), +1.0 EV
  
• Canon PowerShot A520: Manual exposure mode, ISO 400, Default Image Parameters,
  Manual white balance
     
• Lighting: Lighting: Daylight simulation, >98% CRI

Note: the Canon A520 shots were taken before we changed the lights in our fixed studio setup. This explains the different exposure values and pattern of reflections.

Sony DSC-S90	Canon PowerShot A520
ISO 400,1/160 sec, F7.1	ISO 400,1/800 sec, F5
1,798 KB JPEG	689 KB JPEG
Noise, std dev: 3.4	Noise, std dev: 4.6

Again, not a massive difference at ISO 400; in fact the gap has been narrowed even further, with the Canon's image losing out more to noise (and noise reduction) in both color and detail. What I don't like is the combination of heavy noise reduction and strong in-camera sharpening on the S90 image, which has resulted in visible halos around high contrast detail. Fortunately you can turn down the sharpening a touch in P mode. And in any case, the result is perfectly printable at standard print size (say 5x7 inches or less).