These images show the effect of sharpening both in the camera and in Aperture. Images marked "low sharp" are with the S3 set at its lowest sharpening setting, those marked "med sharp" are with the setting in the middle, and those marked "high sharp" are at the maximum.

For Aperture adjustments: "50" = 50% at one pixel. "100" = 100% at 1 pixel. "100 2" = 100% at 2 pixels.

Images taken with a Canon S3 IS at 2816 x 2112 pixels at ISO 100 f4.5 The thumbnails link to images 1024 pixels wide. Those images link to full-size originals with EXIF.
They are all taken at ISO 100, f4.5.