Both Canon SX520 HS and Canon A2400 IS have 16.0 MP resolution sensors but Canon SX520 HS's sensor is 1/2.3' (6.17 x 4.55 mm ) and Canon A2400 IS's sensor is 1/2.3-inch (6.17 x 4.55 mm ).
Since Canon A2400 IS'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 SX520 HS.
Below you can see the SX520 HS and A2400 IS sensor size comparison.
Sensor Size and Resolution Comparison image of Canon SX520 HS and Canon A2400 IS Cameras
Canon SX520 HS and Canon A2400 IS 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
Canon SX520 HS
or the
Canon A2400 IS ,
including hyperfocal distance.
One thing to watch when comparing these two: they have different sensor sizes
(1/2.3' versus 1/2.3-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.
