Olympus E-PL9 has a
16.0MP Four Thirds (17.3 x 13 mm ) sized CMOS sensor and features TruePic VIII processor. On the other hand, Olympus PEN-F has a
20.0MP Four Thirds (17.3 x 13 mm ) sized CMOS sensor and features TruePic VII processor.
Below you can see the E-PL9 and PEN-F sensor size comparison.
Sensor Size and Resolution Comparison image of Olympus E-PL9 and Olympus PEN-F Cameras
Olympus E-PL9 and Olympus PEN-F 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-PL9
or the
Olympus PEN-F ,
including hyperfocal distance.