Both Leica Q 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 Q Typ 116 and A9 sensor size comparison.
Leica Q 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 Q and Sony A9 sensors have been tested by DxO and the results show that A9 has a better overall score of 92, 7 points higher compared to Q Typ 116's score of 85.
Model |
Overall |
Color Depth |
Dynamic Range |
Low-light ISO |
Leica Q |
85 |
24.3 bits |
12.7 Evs |
2221 ISO |
Sony A9 |
92 |
24.9 bits |
13.3 Evs |
3517 ISO |