Both Panasonic GH5 II and Sony a5000 have 20.0 MP resolution sensors but Panasonic GH5 II's sensor is Four Thirds (17.3 x 13 mm ) and Sony a5000's sensor is APS-C (23.2 x 15.4 mm ).
Since Sony a5000'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 Panasonic GH5 II.
Another difference between these two cameras is that Panasonic GH5 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 GH5 II and a5000 sensor size comparison.
Sensor Size and Resolution Comparison image of Panasonic GH5 II and Sony a5000 Cameras
As seen above, Sony a5000 has a 1.6x Larger sensor area than Panasonic GH5 II. Larger sensors give photographer more control on the depth of field and blurry background compared to smaller sensor when shot in 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
Panasonic GH5 II
79
23.7 bits
13.1 Evs
1136 ISO
Sony a5000
79
23.8 bits
13.0 Evs
1089 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 II
or the
Sony a5000 ,
including hyperfocal distance.
One thing to watch when comparing these two: they have different sensor sizes
(Four Thirds versus APS-C),
so compare them at the same framing rather than the same focal length.
Put the same focal length on the smaller sensor and it will show less depth of
field, not more, because it also crops tighter. The calculator shows the
full frame equivalent focal length for each body so you can match the framing.
