Resolution Chart Comparison

Shots here are of our 'version two' resolution chart which provides for measurement of resolution up to 4000 LPH (Lines Per Picture Height). A value of 20 equates to 2000 lines per picture height. For each camera the relevant prime lens was used. The chart is shot at a full range of apertures and the sharpest image selected. Studio light, cameras set to aperture priority (optimum aperture selected), image parameters default. Exposure compensation set to deliver approximately 80% luminance of white area.

Nikon D300 (3.3 KB; 12 MP)	Canon EOS 40D (2.6 MB, 10 MP)
Sony DSLR-A700 (2.6 MB, 12 MP)	Olympus E-3 (3.3 MB; 10 MP)

Nikon D300	Canon EOS 40D
Sony DSLR-A700	Olympus E-3

Nikon D300	Canon EOS 40D
Sony DSLR-A700	Olympus E-3

Nikon D300	Canon EOS 40D
Sony DSLR-A700	Olympus E-3

Measurable results

As you can see from the figures (and crops) above there really is very little difference between ten and twelve megapixels, however the sensor design (anti-alias filter strength), imaging pipeline (demosaicing, sharpening) have a much more significant effect that megapixels alone. The D300's image is the cleanest here with no noticeable moire and almost invisible sharpening artifacts. The DSLR-A700 delivers as much absolute resolution and manages to delve a bit deeper beyond nyquist (to extinction resolution) but seemingly at the expense of some visible moire.