Both Fujifilm Z30 and Pentax K200D have 10.0 MP resolution sensors but Fujifilm Z30's sensor is 1/2.3-inch (6.17 x 4.55 mm ) and Pentax K200D's sensor is APS-C (23.5 x 15.7 mm ).
Since Pentax K200D'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 Fujifilm Z30.
Below you can see the Z30 and K200D sensor size comparison.
Sensor Size and Resolution Comparison image of Fujifilm Z30 and Pentax K200D Cameras
As seen above, Pentax K200D has a 13.1x Larger sensor area than Fujifilm Z30. 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
Fujifilm Z30
or the
Pentax K200D ,
including hyperfocal distance.
One thing to watch when comparing these two: they have different sensor sizes
(1/2.3-inch versus APS-C),
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.
