It is obvious that the the quality of image your camera captures is not determined by Megapixels alone.  The real elements that determine the quality of a camera’s sensors are measured in the ISO Sensitivity of the Sensor, the Signal to Noise Ratio (Measured at 18%), the Dynamic Range, Tonal Range and the Color Sensitivity.

DxO Labs created dxomark.com for members of the digital photographic community who are passionate about image quality – professional photographers, advanced amateurs, photography reviewers and imaging media journalists. While other websites publish information about JPEG image quality, only DxO Labs provides the first publicly-accessible database of objective and in-depth RAW sensor image quality measurements.

From http://www.dxomark.com

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