Panasonic ZS60 has a
18.0MP 1/2.3-inch (6.17 x 4.55 mm ) sized CMOS sensor and features Venus Engine processor. On the other hand, Olympus SZ-31MR iHS has a
16.0MP 1/2.3-inch (6.17 x 4.55 mm ) sized BSI-CMOS sensor and features Dual TruePic V processor.
Below you can see the ZS60 and SZ-31MR iHS sensor size comparison.
Sensor Size and Resolution Comparison image of Panasonic ZS60 and Olympus SZ-31MR iHS Cameras
Panasonic ZS60 and Olympus SZ-31MR iHS 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.
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
Panasonic ZS60
or the
Olympus SZ-31MR iHS ,
including hyperfocal distance.