Panasonic GH1 has a
12.0MP Four Thirds (18.89 x 14.48 mm ) sized CMOS sensor and features Venus Engine HD processor. On the other hand, OM System OM-5 II has a
20.0MP Four Thirds (17.4 x 13 mm ) sized CMOS sensor and features TruePic IX processor.
OM System OM-5 II's sensor provides 8MP more than Panasonic GH1's sensor, which gives a significant advantage in real life. You can print your images larger or crop more freely.
On the other hand, please keep in mind that Max sensor resolution is not the only determinant of resolving power. Factors such as the optical elements, low pass filter, pixel size and sensor technology also affects the final resolution of the captured image.
Below you can see the GH1 and OM-5 Mark II sensor size comparison.
Sensor Size and Resolution Comparison image of Panasonic GH1 and OM System OM-5 II Cameras
As seen above, Panasonic GH1 has a 1.2x Larger sensor area than OM System OM-5 II. Larger sensors give photographer more control on the depth of field and blurry background compared to smaller sensor when shot in same focal length and aperture.
Sensor size sets the circle of confusion, so it drives how much depth of field each
of these bodies gives you at a given aperture. You can calculate it exactly for the
Panasonic GH1
or the
OM System OM-5 II ,
including hyperfocal distance.
