Both Nikon D7100 and Sony A6400 have 24.0 MP resolution sensors but Nikon D7100's sensor is APS-C (23.5 x 15.6 mm ) and Sony A6400's sensor is APS-C (23.5 x 15.6 mm ).
Since Sony A6400'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 Nikon D7100.
Another difference between these two cameras is that Nikon D7100'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 D7100 and A6400 sensor size comparison.
Nikon D7100 and Sony A6400 have the same sensor sizes so they will provide same level of control over the depth of field when used with 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 |
Nikon D7100 |
83 |
24.2 bits |
13.7 Evs |
1256 ISO |
Sony A6400 |
83 |
24.0 bits |
13.6 Evs |
1431 ISO |