FujiFilm S2800HD has a 14.0MP 1/2.3-inch (6.17 x 4.55 mm ) sized CCD sensor . On the other hand, Olympus SZ-30MR has a 16.0MP 1/2.3-inch (6.17 x 4.55 mm ) sized CMOS sensor and features TruePic III+ processor.
Below you can see the S2800HD and SZ-30MR sensor size comparison.
FujiFilm S2800HD and Olympus SZ-30MR 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 Olympus SZ-30MR, it has potential to collect more light on pixel level hence have less noise in low light / High ISO images.