Both Olympus E-M1 and Olympus E-M5 II have 16.0 MP resolution sensors but Olympus E-M1's sensor is Four Thirds (17.3 x 13 mm ) and Olympus E-M5 II's sensor is Four Thirds (17.3 x 13 mm ).
Since Olympus E-M5 II's has a larger sensor area with the same resolution, this means that it also has a larger pixel area hence better light collecting capacity for a given aperture compared to Olympus E-M1.
Below you can see the E-M1 and E-M5 Mark II sensor size comparison.
Olympus E-M1 and Olympus E-M5 II have the same sensor sizes so they will provide same level of control over the depth of field when used with same focal length and aperture.
DxOMark Sensor Scores
At Camera Decision, we also look at Dxo Mark sensors when available as we think it is a good indicator of image quality.
Model |
Overall |
Color Depth |
Dynamic Range |
Low-light ISO |
Olympus E-M1 |
73 |
23.0 bits |
12.7 Evs |
757 ISO |
Olympus E-M5 II |
73 |
23.0 bits |
12.4 Evs |
896 ISO |