Both Panasonic GH5 and Olympus E-M1 II have Four Thirds sized 20.0 MP resolution sensors so sensor size and resolution is not a differentiator between these two cameras.
Another similarity between these two cameras is that both Olympus E-M1 II and Panasonic GH5 sensors lack anti-alias (Low-Pass) filters. 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 GH5 and E-M1 II sensor size comparison.
Sensor Size and Resolution Comparison image of Panasonic GH5 and Olympus E-M1 II Cameras
Panasonic GH5 and Olympus E-M1 II 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
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. Panasonic GH5 and Olympus E-M1 II sensors have been tested by DxO and the results show that E-M1 II has a better overall score of 80, 3 points higher compared to GH5's score of 77.
Model
Overall
Color Depth
Dynamic Range
Low-light ISO
Panasonic GH5
77
23.9 bits
13.0 Evs
807 ISO
Olympus E-M1 II
80
23.7 bits
12.8 Evs
1312 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 GH5
or the
Olympus E-M1 II ,
including hyperfocal distance.
