Both Olympus E-P7 and Olympus E-M10 IV have Four Thirds sized 20.0 MP resolution sensors so sensor size and resolution is not a differentiator between these two cameras.
Another difference between these two cameras is that Olympus E-P7's sensor lacks anti-alias (Low-Pass) filter. Removing anti-alias filter increases the sharpness and level of detail but at the same time, it increases the chance of moiré occurring in certain scenes.
Below you can see the E-P7 and E-M10 IV sensor size comparison.
Sensor Size and Resolution Comparison image of Olympus E-P7 and Olympus E-M10 IV Cameras
Olympus E-P7 and Olympus E-M10 IV 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
Olympus E-P7
or the
Olympus E-M10 IV ,
including hyperfocal distance.
