Nikon S6200 has a
16.0MP 1/2.3-inch (6.17 x 4.55 mm ) sized CCD sensor and features Expeed C2 processor. On the other hand, Canon A1100 IS has a
12.0MP 1/2.3-inch (6.17 x 4.55 mm ) sized CCD sensor and features Digic 4 processor.
Below you can see the S6200 and A1100 IS sensor size comparison.
Nikon S6200 and Canon A1100 IS have the same sensor sizes so they will provide same level of control over the depth of field when used with same focal length and aperture. On the other hand, since Canon A1100 IS has 32% larger pixel area (2.34µm2 vs 1.76µm2) compared to Nikon S6200, it has larger pixel area to collect light hence potential to have less noise in low light / High ISO images.