Sony A7S II has a
12.0MP Full frame (35.6 x 23.8 mm ) sized CMOS sensor and features Bionz X processor. On the other hand, Nikon Z6 III has a
24.0MP Full frame (35.9 x 23.9 mm ) sized Partially-Stacked CMOS sensor and features Expeed 7 processor.
Nikon Z6 III's sensor provides 12MP more than Sony A7S II'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 A7S II and Z6 Mark III sensor size comparison.
Sensor Size and Resolution Comparison image of Sony A7S II and Nikon Z6 III Cameras
Sony A7S II and Nikon Z6 III 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.
Sensor size sets the circle of confusion, so it drives how much depth of field each
of these bodies gives you at a given aperture. You can calculate it exactly for the
Sony A7S II
or the
Nikon Z6 III ,
including hyperfocal distance.
