Olympus E-M1 II has a
20.0MP Four Thirds (17.4 x 13 mm ) sized CMOS sensor and features TruePic VIII processor. On the other hand, Olympus E-3 has a
10.0MP Four Thirds (17.3 x 13 mm ) sized CMOS sensor and features TruePic III processor.
Olympus E-M1 II's sensor provides 10MP more than Olympus E-3'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.
Another difference between these two cameras is that Olympus E-M1 II's sensor lacks anti-alias (Low-Pass) filter. Removing anti-alias filter increases the sharpness and level of detail but at the same time, it increases the chance of moiré occurring in certain scenes.
Below you can see the E-M1 II and E-3 sensor size comparison.
Sensor Size and Resolution Comparison image of Olympus E-M1 II and Olympus E-3 Cameras
Olympus E-M1 II and Olympus E-3 have almost the same sensor size, so neither of them has any significant advantage over the other in terms of providing control over depth of field when used with the same focal length and aperture.
DxOMark Sensor Scores
Both Olympus E-M1 II and Olympus E-3 sensors have been tested by DxoMark. DxoMark scores camera sensors for color depth (DXO Portrait), dynamic range (DXO Landscape) and low-light sensitivity (DXO Sports), and also gives them an overall score. Of the two cameras that we are comparing, E-M1 II has scored 80, 24 points higher than E-3.
Model
Overall
Color Depth
Dynamic Range
Low-light ISO
Olympus E-M1 II
80
23.7 bits
12.8 Evs
1312 ISO
Olympus E-3
56
21.6 bits
10.5 Evs
571 ISO
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
Olympus E-M1 II
or the
Olympus E-3 ,
including hyperfocal distance.