Panasonic ZS7 has a
12.0MP 1/2.3-inch (6.08 x 4.56 mm ) sized CCD sensor and features Venus Engine HD II processor. On the other hand, Ricoh GXR P10 28-300mm 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 ZS7 and GXR P10 28-300mm F3.5-5.6 VC sensor size comparison.
Panasonic ZS7 and Ricoh GXR P10 28-300mm 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.