Pentax RZ10 has a
14.0MP 1/2.3-inch (6.08 x 4.56 mm ) sized CCD sensor . On the other hand, Ricoh CX3 has a
10.0MP 1/2.3-inch (6.17 x 4.55 mm ) sized BSI-CMOS sensor and features Smooth Imaging Engine IV processor.
Below you can see the RZ10 and CX3 sensor size comparison.
Sensor Size and Resolution Comparison image of Pentax RZ10 and Ricoh CX3 Cameras
Pentax RZ10 and Ricoh CX3 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
Pentax RZ10
or the
Ricoh CX3 ,
including hyperfocal distance.