Nikon D4s has a
16.0MP Full frame (36 x 23.9 mm ) sized CMOS sensor and features Expeed 4 processor. On the other hand, Sony A9 II has a
24.0MP Full frame (35.6 x 23.8 mm ) sized Stacked BSI-CMOS sensor and features BIONZ X processor.
Sony A9 II's sensor provides 8MP more than Nikon D4s'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.
Below you can see the D4s and A9 Mark II sensor size comparison.
Nikon D4s and Sony A9 II 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. Nikon D4s and Sony A9 II sensors have been tested by DxO and the results show that A9 Mark II has a better overall score of 93, 4 points higher compared to D4s's score of 89.
Model |
Overall |
Color Depth |
Dynamic Range |
Low-light ISO |
Nikon D4s |
89 |
24.4 bits |
13.3 Evs |
3074 ISO |
Sony A9 II |
93 |
25.0 bits |
14.0 Evs |
3434 ISO |