Both Olympus E-520 and Olympus E-420 have Four Thirds sized 10.0 MP resolution sensors so sensor size and resolution is not a differentiator between these two cameras.
Below you can see the E-520 and E-420 sensor size comparison.
Olympus E-520 and Olympus E-420 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
DxOMark is a benchmark that scientifically assesses image quality of camera sensors. It 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. Olympus E-520 and Olympus E-420 sensors have been tested by DxO and the results show that E-420 has a better overall score of 56, 1 points higher compared to E-520's score of 55.
Model |
Overall |
Color Depth |
Dynamic Range |
Low-light ISO |
Olympus E-520 |
55 |
21.4 bits |
10.4 Evs |
548 ISO |
Olympus E-420 |
56 |
21.5 bits |
10.4 Evs |
527 ISO |