Both Canon ELPH 500 HS and Canon G16 have 12.0 MP resolution sensors but Canon ELPH 500 HS's sensor is 1/2.3-inch (6.17 x 4.55 mm ) and Canon G16's sensor is 1/1.7-inch (7.44 x 5.58 mm ).
Since Canon G16'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 Canon ELPH 500 HS.
Below you can see the ELPH 500 HS and G16 sensor size comparison.
Sensor Size and Resolution Comparison image of Canon ELPH 500 HS and Canon G16 Cameras
As seen above, Canon G16 has a 1.5x Larger sensor area than Canon ELPH 500 HS. 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
Canon ELPH 500 HS
or the
Canon G16 ,
including hyperfocal distance.
One thing to watch when comparing these two: they have different sensor sizes
(1/2.3-inch versus 1/1.7-inch),
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.