Both Sony W510 and Panasonic GF5 have 12.0 MP resolution sensors but Sony W510's sensor is 1/2.3-inch (6.17 x 4.55 mm ) and Panasonic GF5's sensor is Four Thirds (17.3 x 13 mm ).
Since Panasonic GF5's has a larger sensor area with the same resolution, this means that it also has a larger pixel area hence better light collecting capacity for a given aperture compared to Sony W510.
Below you can see the W510 and GF5 sensor size comparison.
Sensor Size and Resolution Comparison image of Sony W510 and Panasonic GF5 Cameras
As seen above, Panasonic GF5 has a 8.0x Larger sensor area than Sony W510. Larger sensors give photographer more control on the depth of field and blurry background compared to smaller sensor when shot in 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
Sony W510
or the
Panasonic GF5 ,
including hyperfocal distance.
One thing to watch when comparing these two: they have different sensor sizes
(1/2.3-inch versus Four Thirds),
so compare them at the same framing rather than the same focal length.
Put the same focal length on the smaller sensor and it will show less depth of
field, not more, because it also crops tighter. The calculator shows the
full frame equivalent focal length for each body so you can match the framing.