Both Samsung ST6500 and Casio EX-ZR800 have 1/2.3-inch sized 16.0 MP resolution sensors so sensor size and resolution is not a differentiator between these two cameras.
Below you can see the ST6500 and EX-ZR800 sensor size comparison.
Sensor Size and Resolution Comparison image of Samsung ST6500 and Casio EX-ZR800 Cameras
Samsung ST6500 and Casio EX-ZR800 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.
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
Samsung ST6500
or the
Casio EX-ZR800 ,
including hyperfocal distance.
