Ricoh CX4 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. On the other hand, Canon SX30 IS has a
14.0MP 1/2.3-inch (6.17 x 4.55 mm ) sized CCD sensor and features Digic 4 processor.
Below you can see the CX4 and SX30 IS sensor size comparison.
Ricoh CX4 and Canon SX30 IS 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.