FujiFilm S2800HD has a
14.0MP 1/2.3-inch (6.17 x 4.55 mm ) sized CCD sensor . On the other hand, Nikon S8200 has a
16.0MP 1/2.3-inch (6.17 x 4.55 mm ) sized BSI-CMOS sensor and features Expeed C2 processor.
Below you can see the S2800HD and S8200 sensor size comparison.
FujiFilm S2800HD and Nikon S8200 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 FujiFilm S2800HD has 15% larger pixel area compared to Nikon S8200, it has potential to collect more light on pixel level hence have less noise in low light / High ISO images.