Both Sony a5000 and Olympus E-M10 IV have 20.0 MP resolution sensors but Sony a5000's sensor is APS-C (23.2 x 15.4 mm ) and Olympus E-M10 IV's sensor is Four Thirds (17.4 x 13 mm ).
Since Sony a5000'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 Olympus E-M10 IV.
Below you can see the a5000 and E-M10 IV sensor size comparison.
Sensor Size and Resolution Comparison image of Sony a5000 and Olympus E-M10 IV Cameras
As seen above, Sony a5000 has a 1.6x Larger sensor area than Olympus E-M10 IV. 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 a5000
or the
Olympus E-M10 IV ,
including hyperfocal distance.
One thing to watch when comparing these two: they have different sensor sizes
(APS-C 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.
