Nikon D3S has a
12.0MP Full frame (36 x 23.9 mm ) sized CMOS sensor and features Expeed processor. On the other hand, Canon 1D X III has a
20.0MP Full frame (36 x 24 mm ) sized CMOS sensor and features Digic X processor.
Canon 1D X III's sensor provides 8MP more than Nikon D3S'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 D3S and 1D X MIII sensor size comparison.
Sensor Size and Resolution Comparison image of Nikon D3S and Canon 1D X III Cameras
Nikon D3S and Canon 1D X 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.
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 D3S and Canon 1D X III sensors have been tested by DxO and the results show that 1D X MIII has a better overall score of 91, 9 points higher compared to D3S's score of 82.
Model
Overall
Color Depth
Dynamic Range
Low-light ISO
Nikon D3S
82
23.5 bits
12.0 Evs
3253 ISO
Canon 1D X III
91
24.2 bits
14.5 Evs
3248 ISO
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
Nikon D3S
or the
Canon 1D X III ,
including hyperfocal distance.
