FujiFilm S2800HD has a
14.0MP 1/2.3-inch (6.17 x 4.55 mm ) sized CCD sensor . On the other hand, Panasonic ZS30 has a
18.0MP 1/2.3-inch (6.17 x 4.55 mm ) sized CMOS sensor .
Below you can see the S2800HD and ZS30 sensor size comparison.
FujiFilm S2800HD and Panasonic ZS30 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 30% larger pixel area compared to Panasonic ZS30, it has potential to collect more light on pixel level hence have less noise in low light / High ISO images.