Pentax Efina has a
14.0MP 1/2.3-inch (6.17 x 4.55 mm ) sized CCD sensor . On the other hand, FujiFilm Z800EXR has a
12.0MP 1/2-inch (6.4 x 4.8 mm ) sized CCD sensor and features EXR processor.
Below you can see the Efina and Z800EXR sensor size comparison.
Pentax Efina and FujiFilm Z800EXR have almost the same sensor size, so neither of them has any significant advantage over the other in terms of providing control over depth of field when used with the same focal length and aperture.