Both Leica M10 and Sony A9 have Full frame sized 24.0 MP resolution sensors so sensor size and resolution is not a differentiator between these two cameras.
Below you can see the M10 and A9 sensor size comparison.
Leica M10 and Sony A9 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. Leica M10 and Sony A9 sensors have been tested by DxO and the results show that A9 has a better overall score of 92, 6 points higher compared to M10's score of 86.
Model |
Overall |
Color Depth |
Dynamic Range |
Low-light ISO |
Leica M10 |
86 |
24.4 bits |
13.3 Evs |
2133 ISO |
Sony A9 |
92 |
24.9 bits |
13.3 Evs |
3517 ISO |