Ricoh WG-1000 has a
16.0MP 1/2.3-inch (6.17 x 4.55 mm ) sized BSI-CMOS sensor . On the other hand, FujiFilm S1800 has a
12.0MP 1/2.3-inch (6.17 x 4.55 mm ) sized CCD sensor .
Below you can see the WG-1000 and S1800 sensor size comparison.
Sensor Size and Resolution Comparison image of Ricoh WG-1000 and FujiFilm S1800 Cameras
Ricoh WG-1000 and FujiFilm S1800 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 S1800 has 32% larger pixel area (2.34µm 2 vs 1.76µm 2 ) compared to Ricoh WG-1000, it has larger pixel area to collect light hence potential to have less noise in low light / High ISO images.
Sensor size sets the circle of confusion, so it drives how much depth of field each
of these bodies gives you at a given aperture. You can calculate it exactly for the
Ricoh WG-1000
or the
FujiFilm S1800 ,
including hyperfocal distance.