Both Canon 1D X III and Nikon S3700 have 20.0 MP resolution sensors but Canon 1D X III's sensor is Full frame (36 x 24 mm ) and Nikon S3700's sensor is 1/2.3' (6.17 x 4.55 mm ).
Since Canon 1D X III'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 S3700.
Below you can see the 1D X MIII and S3700 sensor size comparison.
Sensor Size and Resolution Comparison image of Canon 1D X III and Nikon S3700 Cameras
As seen above, Canon 1D X III has a 30.8x Larger sensor area than Nikon S3700. 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.
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
Canon 1D X III
or the
Nikon S3700 ,
including hyperfocal distance.
One thing to watch when comparing these two: they have different sensor sizes
(Full frame versus 1/2.3' ),
so compare them at the same framing rather than the same focal length.
Put the same focal length on the smaller sensor and it will show less depth of
field, not more, because it also crops tighter. The calculator shows the
full frame equivalent focal length for each body so you can match the framing.
