Both Sony A6400 and Sony A7c have 24.0 MP resolution sensors but Sony A6400's sensor is APS-C (23.5 x 15.6 mm ) and Sony A7c's sensor is Full frame (35.8 x 23.8 mm ).
Since Sony A7c'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 Sony A6400.
Below you can see the A6400 and A7c sensor size comparison.
As seen above, Sony A7c has a 2.3x Larger sensor area than Sony A6400. 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. Sony A6400 and Sony A7c sensors have been tested by DxO and the results show that A7c has a better overall score of 95, 12 points higher compared to A6400's score of 83.
Model |
Overall |
Color Depth |
Dynamic Range |
Low-light ISO |
Sony A6400 |
83 |
24.0 bits |
13.6 Evs |
1431 ISO |
Sony A7c |
95 |
25.0 bits |
14.7 Evs |
3407 ISO |