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.

Olympus E-30 (7.0 MB; 12 MP) Canon EOS 50D (2.6 MB; 10 MP)
Nikon D300 (3.3 KB; 12 MP) Olympus E-3 (4.7 MB; 10 MP)
Panasonic DMC-G1 (3,615 KB; 10 MP)  

Olympus E-30 Canon EOS 50D
Nikon D300 Olympus E-3

Olympus E-30 Canon EOS 50D
Nikon D300 Olympus E-3

Olympus E-30 Canon EOS 50D
Nikon D300 Olympus E-3

Measurable results

Camera Measurement
Olympus E-30 Horizontal LPH * 2150  2550 
Vertical LPH * 1900  2300 
Canon EOS 50D Horizontal LPH 2250  2700 
Vertical LPH 2200  2700 
Nikon D300 Horizontal LPH 2200  2600 
Vertical LPH 2100  2600 
Olympus E-3 Horizontal LPH * 2100  2400 
Vertical LPH * 1800  2200 
Panasonic G1 Horizontal LPH 2350  2700 
Vertical LPH 2300  2550 

* Moiré is visible
+ Chart maximum
LPH Lines per Picture Height (to allow for different aspect ratios the measurement is the same for horizontal and vertical)
Absolute resolution Point at which all lines of a resolution bar are still visible and defined, beyond this resolution loss of detail occurs (below Nyquist frequency).
Extinction resolution Detail beyond camera's definition (becomes aliased)

The difference between them isn't huge, but the E-30 squeezes a little more resolution out of its sensor than the E-3, though in terms of pure numbers the it cannot quite keep up with the competition in this comparison. The difference is marginal though and would would hardly be noticeable in a real-life shot.