Both Panasonic GH4 and Olympus E-M1 have Four Thirds sized 16.0 MP resolution sensors so sensor size and resolution is not a differentiator between these two cameras.
Below you can see the GH4 and E-M1 sensor size comparison.
Sensor Size and Resolution Comparison image of Panasonic GH4 and Olympus E-M1 Cameras
Panasonic GH4 and Olympus E-M1 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
Both Panasonic GH4 and Olympus E-M1 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, GH4 has scored 74, 1 points higher than E-M1.
Model
Overall
Color Depth
Dynamic Range
Low-light ISO
Panasonic GH4
74
23.2 bits
12.8 Evs
791 ISO
Olympus E-M1
73
23.0 bits
12.7 Evs
757 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
Panasonic GH4
or the
Olympus E-M1 ,
including hyperfocal distance.
