Both Nikon S640 and FujiFilm Z800EXR have 12.0 MP resolution sensors but Nikon S640's sensor is 1/2.3-inch (6.08 x 4.56 mm ) and FujiFilm Z800EXR's sensor is 1/2-inch (6.4 x 4.8 mm ).
Since FujiFilm Z800EXR's has a larger sensor area with the same resolution, this means that it also has a larger pixel area hence better light collecting capacity for a given aperture compared to Nikon S640.
Below you can see the S640 and Z800EXR sensor size comparison.
Sensor Size and Resolution Comparison image of Nikon S640 and FujiFilm Z800EXR Cameras
As seen above, FujiFilm Z800EXR has a 1.1x Larger sensor area than Nikon S640. Larger sensors give photographer more control on the depth of field and blurry background compared to smaller sensor when shot in same focal length and aperture.
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
Nikon S640
or the
FujiFilm Z800EXR ,
including hyperfocal distance.
One thing to watch when comparing these two: they have different sensor sizes
(1/2.3-inch versus 1/2-inch),
so compare them at the same framing rather than the same focal length.
Put the same focal length on the smaller sensor and it will show less depth of
field, not more, because it also crops tighter. The calculator shows the
full frame equivalent focal length for each body so you can match the framing.
