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 SX30 IS has a
14.0MP 1/2.3-inch (6.17 x 4.55 mm ) sized CCD sensor and features Digic 4 processor.
Below you can see the D3S and SX30 IS sensor size comparison.
As seen above, Nikon D3S has a 30.7x Larger sensor area than Canon SX30 IS. 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.