Both Nikon S620 and Canon ELPH 500 HS have 1/2.3-inch sized 12.0 MP resolution sensors so sensor size and resolution is not a differentiator between these two cameras.
Below you can see the S620 and ELPH 500 HS sensor size comparison.
Sensor Size and Resolution Comparison image of Nikon S620 and Canon ELPH 500 HS Cameras
Nikon S620 and Canon ELPH 500 HS 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.
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
Nikon S620
or the
Canon ELPH 500 HS ,
including hyperfocal distance.
