FujiFilm S2800HD has a 14.0MP 1/2.3-inch (6.17 x 4.55 mm ) sized CCD sensor . On the other hand, Nikon S9700 has a 16.0MP 1/2.3-inch (6.17 x 4.55 mm ) sized BSI-CMOS sensor .
Below you can see the S2800HD and S9700 sensor size comparison.
FujiFilm S2800HD and Nikon S9700 have 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 S9700, it has potential to collect more light on pixel level hence have less noise in low light / High ISO images.