Olympus SZ-30MR has a 16.0MP 1/2.3-inch (6.17 x 4.55 mm ) sized CMOS sensor and features TruePic III+ processor. On the other hand, Canon SX260 HS has a 12.0MP 1/2.3-inch (6.17 x 4.55 mm ) sized BSI-CMOS sensor and features Digic 5 processor.
Below you can see the SZ-30MR and SX260 HS sensor size comparison.
Olympus SZ-30MR and Canon SX260 HS have sensor sizes so they will provide same level of control over the depth of field when used with same focal length and aperture. On the other hand, since Canon SX260 HS has 32% larger pixel area (2.34µm2 vs 1.76µm2) compared to Olympus SZ-30MR, it has larger pixel area to collect light hence potential to have less noise in low light / High ISO images.