Panasonic GX850 has a
16.0MP Four Thirds (17.3 x 13 mm ) sized CMOS sensor and features Venus Engine processor. On the other hand, Sony a5100 has a
24.0MP APS-C (23.5 x 15.6 mm ) sized CMOS sensor and features Bionz X processor.
Sony a5100's sensor provides 8MP more than Panasonic GX850's sensor, which gives a significant advantage in real life. You can print your images larger or crop more freely.
On the other hand, please keep in mind that Max sensor resolution is not the only determinant of resolving power. Factors such as the optical elements, low pass filter, pixel size and sensor technology also affects the final resolution of the captured image.
Another difference between these two cameras is that Panasonic GX850'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 GX850 and a5100 sensor size comparison.
As seen above, Sony a5100 has a 1.6x Larger sensor area than Panasonic GX850. 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
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 GX850 and Sony a5100 sensors have been tested by DxO and the results show that a5100 has a better overall score of 80, 7 points higher compared to GX850's score of 73.
Model |
Overall |
Color Depth |
Dynamic Range |
Low-light ISO |
Panasonic GX850 |
73 |
23.2 bits |
13.3 Evs |
586 ISO |
Sony a5100 |
80 |
23.8 bits |
12.7 Evs |
1347 ISO |